Mopar1973Man

DTC P0222: IDLE VALIDATION SIGNALS BOTH LOW Monitor & Set Conditions Idle validation signals are monitored when the ignition is on and the engine is running. DTC P0222 may be stored if Engine Control Module (ECM) senses no voltage signal or the same voltage from Idle Validation Switch (IVS) No. 1 and IVS No. 2. DTC P0223 may be stored if ECM senses the same voltage from IVS No. 1 and IVS No. 2. Possible Causes Accelerator Pedal Position Switch (APPS) Idle Validation Switch (IVS) No. 2 Harness Short To Ground APPS IVS No. 2 Shorted To APPS Return Circuit APPS IVS No. 2 Shorted To APPS Sensor Ground IVS No. 2 Open Between APPS And ECM Harness Connectors APPS IVS No. 1 Shorted To APPS Sensor Ground APPS IVS No. 1 Shorted To APPS Return Circuit APPS IVS No. 1 Harness Short To Ground IVS No. 1 Open Between APPS And ECM Harness Connectors IVS No. 1 Circuit Open ECM Testing 1. Turn ignition off. Disconnect APPS harness connector. APPS is located on a bracket, just above fuel injection pump. Check for poor connection/terminal contact at APPS harness connector. Repair as necessary. Start engine and allow the engine to idle. Using DVOM, measure voltage between ground and terminal No. 6 (Brown/Orange wire) on APPS connector. This is the IVS No. 1 circuit. If the voltage is greater than 4.5 volts, go to next step. If the voltage is 5.5 volts or less, go to step 8. 2. With engine idling, using DVOM, measure voltage between ground and terminal No. 2 (Light Green/Dark Blue wire) on APPS harness connector. This is the IVS No. 2 circuit. If the voltage is 4.5 volts or less, go to next step. If the voltage is greater than 4.5 volts, the test is complete. 3. Turn ignition off. Check for continuity between ground and terminal No. 2 (Light Green/Dark Blue wire) on APPS harness connector. If continuity exists, go to next step. If continuity does not exist, go to step 7. 4. Ensure ignition is off and APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for continuity between ground and terminal No. 2 (Light Green/Dark Blue wire) on APPS harness connector. If continuity exists, repair short to ground in Light Green/Dark Blue wire between APPS and ECM. If continuity does not exist, go to next step. 5. Ensure ignition is off. Ensure APPS harness connector and ECM harness connector are still disconnected. Check for continuity between terminal No. 2 (Light Green/Dark Blue wire) and terminal No. 4 (Black/Yellow wire) on APPS harness connector. If continuity exists, repair short between Light Green/Dark Blue wire and Black/Yellow wire. If continuity does not exist, go to next step. 6. Ensure APPS harness connector and ECM harness connector are still disconnected. Check for continuity between terminal No. 2 (Light Green/Dark Blue wire) and terminal No. 1 (Black/Light Blue wire) on APPS harness connector. If continuity exists, repair short between Light Green/Dark Blue wire and Black/Light Blue wire. If continuity does not exist, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 7. Ensure ignition is off and APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check continuity of Light Green/Dark Blue wire between terminal No. 2 on APPS harness connector and terminal No. 16 on ECM harness connector. If continuity exists, the test is complete. If continuity does not exist, repair open in Light Green/Dark Blue wire between APPS and ECM. 8. Turn ignition off. Ensure APPS harness connector is still disconnected. Check for continuity between ground and terminal No. 6 (Brown/Orange wire) on APPS harness connector. If continuity exists, go to next step. If continuity does not exist, go to step 12. 9. Ensure ignition is off and APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50- pin connector. Check for poor connection/terminal contact at ECM harness connector. Check for continuity between terminal No. 6 (Brown/Orange wire) and terminal No. 1 (Black/Light Blue wire) on APPS harness connector. If continuity exists, repair short between Brown/Orange wire and Black/Light Blue wire. If continuity does not exist, go to next step. 10. Ensure APPS harness connector and ECM harness connector are still disconnected. Check for continuity between terminal No. 6 (Brown/Orange wire) and terminal No. 4 (Black/Yellow wire) on APPS harness connector. If continuity exists, repair short between Brown/Orange wire and Black/Yellow wire. If continuity does not exist, go to next step. 11. Ensure APPS harness connector and ECM harness connector are still disconnected. Check for continuity between ground and terminal No. 6 (Brown/Orange wire) on APPS harness connector. If continuity exists, repair short to ground in Brown/Orange wire. If continuity does not exist, the test is complete. 12. Ensure ignition is off and APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for poor connection/terminal contact at ECM harness connector. Repair as necessary. Check Brown/Orange wire for continuity between terminal No. 6 on APPS harness connector and terminal No. 1 on ECM harness connector. If continuity exists, the test is complete. If continuity does not exist, repair open in Brown/Orange wire between APPS and ECM.

DTC P0219: CRANKSHAFT POSITION SENSOR OVERSPEED SIGNAL 1. Turn ignition on with engine off. Using scan tool, read engine RPM. If engine RPM is zero RPM with engine off, go to next step. If engine RPM is more than zero RPM with engine off, replace ECM. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Perform TEST VER-2A . 2. Turn ignition off. Remove air intake hoses from turbocharger and check turbocharger for signs of leaking oil seals. If no sign of leaking oil seals exist, go to next step. If signs of leaking oil seals exist, replace turbocharger. Perform TEST VER-2A . If signs of leaking oil seals exist, the charge air cooler and air intake system should be cleaned to prevent engine overspeed. 3. Ensure ignition is off. Disconnect CKP sensor connector. CKP sensor is located on driver's side of cylinder block, just behind the starter. Fig. 35 . Inspect CKP sensor for damage electrical terminals. If CKP sensor electrical terminals are okay, go to next step. If CKP sensor electrical terminals are damaged, replace CKP sensor. Perform TEST VER-2A . 4. Ensure ignition is off. Using scan tool in lab scope mode, connect lab scope lead to terminal "C" (Gray wire) on CKP sensor connector. Start engine and allow engine to idle. Check CKP sensor pattern in 10 millisecond range. If CKP sensor pattern is irregular, go to next step. If CKP sensor pattern is okay, shut engine off. Disconnect lab scope leads and reinstall CKP sensor connector. Check for use of alternate fuel such as starting fluid or propane, overspeed condition while going down hill, incorrect engine RPM reading, damaged ECM terminals, defective CKP sensor or tone wheel for CKP sensor. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Tone wheel for CKP sensor is bolted to the crankshaft and aligns with opening for CKP sensor on cylinder block. Repair or replace components as necessary. Perform TEST VER-2A . 5. Shut engine off. Ensure ignition is off. Disconnect negative battery cables. Remove starter for access to CKP sensor. Remove retaining bolt and CKP sensor. Inspect tone wheel for CKP sensor for damage. Tone wheel for CKP sensor is bolted to the crankshaft and aligns with opening for CKP sensor on cylinder block. If tone wheel is okay, replace CKP sensor. Perform TEST VER-2A . If tone wheel is defective, replace tone wheel. Perform TEST VER-2A .

DTC P0217: DECREASED ENGINE PERFORMANCE DUE TO ENGINE OVERHEAT CONDITION Monitor & Set Conditions Decreased engine performance due to engine overheat condition is monitored with ignition on and engine running. DTC will set when coolant temperature signal indicates coolant temperature has exceeded the engine protection limit. Possible Causes ECT Sensor Testing Start engine and warm engine to normal operating temperature. Using temperature probe, measure engine temperature near ECT sensor. ECT sensor is located at front of cylinder head, near thermostat housing. Using DRBIII(R) scan tool, read engine coolant temperature. Compare temperature probe reading with scan tool reading. If engine temperature and engine coolant temperature displayed on scan tool are within 10°F of each other, test is complete. If engine temperature and engine coolant temperature displayed on scan tool are not within 10°F of each other, perform DTC P0117: ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE TOO LOW test.

DTC P0216: VP44 FUEL INJECTION PUMP TIMING FAILURE Monitor & Set Conditions Fuel injection pump operation is monitored with ignition on. DTC will set when the engine speed is greater than 300 RPM, fuel command 5 mm3/str and timing command within a certain window. Possible Causes Other DTCs Fuel Injection Pump Gear Alignment Fuel Filter Restriction Transfer Pump Inlet Restriction Fuel Injection Pump Testing 1. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for engine DTCs. If DTC P0336, P1287 or P1690 is set, diagnose those DTC(s) first. See DIAGNOSTIC TROUBLE CODE DEFINITIONS. If DTC P0336, P1287 and P1690 are not set, go to next step. 2. Using scan tool, observe FREEZE FRAME data. Try to duplicate conditions recorded in FREEZE FRAME data. Using scan tool, check for DTCs. If Good Trip Counter changes to zero, go to next step. If Good Trip Counter does not change to zero, the test is complete. 3. Turn ignition off. Check for proper fuel injection pump timing and alignment of fuel injection pump drive gear. See FUEL INJECTION PUMP TIMING in ON-VEHICLE ADJUSTMENTS - RAM PICKUP - DIESEL article. If proper fuel injection pump timing and/or alignment of the fuel injection pump drive gear exists, go to next step. If fuel injection pump timing and alignment of fuel injection pump drive gear are not correct, adjust as necessary. 4. Check fuel pressure drop across fuel filter. See FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - RAM PICKUP - DIESEL article. If fuel pressure drop is as specified, go to next step. If fuel pressure drop is not as specified, check for restriction and repair as necessary. 5. Check transfer pump inlet for a restriction. See FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - RAM PICKUP - DIESEL article. If transfer pump inlet restriction is acceptable, replace fuel injection pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If transfer pump inlet restriction is not acceptable, repair transfer pump inlet line restriction

DTC P0215: FUEL INJECTION PUMP CONTROL CIRCUIT Monitor & Set Conditions Fuel injection pump operation is monitored with ignition on. DTC will set if no power is detected at the fuel injection pump controller with the ignition on. Possible Causes Fuel Injection Pump Relay Ground Circuit Open Fuel Injection Pump Relay ECM Ground Circuit(s) Open Fuel Injection Pump Relay Control Circuit Open Fuel Injection Pump Relay Control Circuit Shorted To Ground ECM Testing 1. Turn ignition off. Remove fuel injection pump relay from Power Distribution Center (PDC). PDC is located at driver's side front corner of engine compartment. Fuel injection pump relay may also be referred to as fuel pump relay. Connect a 12-volt test light between battery voltage and cavity No. 85 (Black wire) in PDC for fuel pump relay. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open in Black wire between cavity No. 85 in PDC and ground connection. The ground connection is located on driver's side fender panel. 2. Note which terminals on fuel pump relay correspond with cavities in PDC. Using DVOM, measure resistance between terminals on fuel pump relay that correspond with cavities No. 85 and 86 in PDC. If the resistance of fuel pump relay 40-100 ohms, go to next step. If resistance is not 40-100 ohms, replace fuel pump relay. 3. Ensure ignition is off. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Connect test light between battery voltage and terminals No. 30 and No. 49 (Black/Tan wires) on ECM harness connector. If test light illuminates brightly at both terminals, go to next step. If test light does not illuminate brightly at any terminal, repair open ground circuit on Black/Tan wire between ECM and ground connection. The ground connection is located at the ground connection for negative battery terminal. 4. Ensure fuel pump relay is still removed from PDC and ECM harness connector is still disconnected. Using DVOM, measure resistance of Brown/White wire between cavity No. 86 in PDC for fuel pump relay and terminal No. 36 on ECM harness connector. If resistance is less than 10 ohms, go to next step. If resistance is 10 ohms or greater, repair open in Brown/White wire between PDC and ECM. 5. Ensure fuel pump relay is still removed from PDC and ECM harness connector is still disconnected. Using DVOM, measure resistance between ground and cavity No. 86 (Brown/White wire) in PDC for fuel pump relay. If resistance is 100 ohms or greater, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If resistance is less than 100 ohms, repair short to ground in Brown/White wire between PDC and ECM.

DTC P0181: FUEL INJECTION PUMP FAILURE Monitor & Set Conditions Fuel injection pump operation is monitored with ignition on. DTC will set if a high or low voltage is detected at the fuel temperature sensor signal circuit inside the fuel injection pump controller. Possible Causes Injection Pump - Engine Running Injection Pump - Engine Off Testing 1. Turn ignition on with engine off. Using DRBIII(R) scan tool, erase any stored engine DTCs. Start engine and allow the engine to idle for one minute. Using scan tool, read engine DTCs. If DTC P0181 does not exist, go to next step. If DTC P0181 exists, replace fuel injection pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 2. Turn ignition off. Turn ignition on with engine off. Using scan tool, clear engine DTCs. Check for engine DTCs with ignition on and engine off. If DTC P0181 does not exist, the test is complete. If DTC P0181 exists, replace fuel injection pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

DTC P0180: FUEL INJECTION PUMP TEMP OUT OF RANGE Monitor & Set Conditions Fuel injection pump temperature is monitored when the engine is running. DTC will set if fuel temperature is out of normal pump operating range. Possible Causes Injection Pump - Engine Running Injection Pump - Engine Off Testing 1. Turn ignition on with engine off. Using DRBIII(R) scan tool, clear engine DTCs. Start engine and allow the engine to idle for one minute. Using scan tool, check for engine DTCs. If DTC P0180 does not exist, go to next step. If DTC P0180 exists, replace fuel injection pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 2. Turn ignition off. Turn ignition on with engine off. Using scan tool, clear engine DTCs. Check for engine DTCs with ignition on and engine off. If DTC P0180 exists, replace fuel injection pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If DTC P0180 does not exist, the test is complete.

DTC P0178: WATER IN FUEL TEMPERATURE SENSOR TOO LOW Monitor & Set Conditions Water-In-Fuel (WIF) sensor circuit is monitored with ignition on. DTC will set if low WIF signal circuit voltage is detected at Engine Control Module (ECM). Possible Causes Other DTC Present - P1488 Other DTC Present - P0562 WIF Sensor Signal Circuit Shorted To Ground WIF Sensor Signal Circuit Shorted To Sensor Ground WIF Sensor ECM Testing 1. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for engine DTCs. If DTC P1488 exists, perform DTC P1488: AUXILIARY 5 VOLT OUTPUT TOO LOW test. If DTC P1488 does not exist, go to next step. 2. If DTC P0562 exists, perform DTC P0562: CHARGING SYSTEM VOLTAGE TOO LOW test. If DTC P0562 does not exist, go to next step. 3. Turn ignition off. Disconnect WIF sensor harness connector. WIF sensor is located at the bottom of fuel filter/water separator on driver's side of the engine, just behind fuel injection pump. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50- pin connector. Using DVOM, measure resistance between ground and terminal "B" (Dark Green/Red wire) on WIF sensor harness connector. If resistance is 100 ohms or greater, go to next step. If resistance is less than 100 ohms, repair short to ground in Dark Green/Red wire between WIF sensor and ECM. 4. Ensure ignition is off. Ensure WIF sensor harness connector and ECM harness connector are still disconnected. Using DVOM, measure resistance between terminals "A" (Black/Light Blue wire) and "B" (Dark Green/Red wire) on WIF sensor connector. If resistance is 100 ohms or greater, go to next step. If resistance is less than 100 ohms, repair short between Black/Light Blue wire and Dark Green/Red wire between ECM and WIF sensor. 5. Ensure ignition is off. Reconnect ECM harness connector. Ensure WIF sensor connector is still disconnected. Turn ignition on with engine off. Using DVOM, measure voltage between ground and terminal "B" (Dark Green/Red wire) on WIF sensor harness connector. If the voltage is not 4.5-5.5 volts, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If the voltage is 4.5-5.5 volts, replace WIF sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

DTC P0177: WATER IN FUEL Monitor & Set Conditions Water-In-Fuel (WIF) sensor circuit is monitored with ignition on. DTC will set if WIF sensor indicates the water in the fuel filter needs to be drained. Possible Causes Water-In-Fuel (WIF) Sensor WIF Sensor Signal Circuit Short To Ground Testing 1. Turn ignition on with engine off. Disconnect WIF sensor harness connector and note operation of WATER-IN-FUEL light. WIF sensor is located at bottom of fuel filter/water separator on driver's side of engine, just behind fuel injection pump. WATER-IN-FUEL light is located on instrument panel, just below the tachometer. If WATER-IN-FUEL light is off, go to next step. If WATER-IN-FUEL light remains on, perform DTC P0178: WATER IN FUEL TEMPERATURE SENSOR TOO LOW test. 2. Turn ignition off. Note location of drain valve and drain hose on fuel filter/water separator. Place drain pan below drain hose. Pull handle on drain valve upward and allow water to drain from fuel filter/water separator. Release handle on drain valve. Reinstall WIF sensor harness connector. Turn ignition on with engine off and note operation of WATER-IN-FUEL light. If WATER-IN-FUEL light remains on, replace WIF sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If WATER-INFUEL light is off, test is complete.

DTC P0168: HIGH INJECTION PUMP FUEL TEMP Monitor & Set Conditions Engine performance is monitored with the engine running. DTC will set if fuel temperature sensor signal indicates fuel temperature has exceeded the engine protection and/or pump protection limit. Possible Causes Overflow Valve Fuel Injection Pump Module Testing 1. Test operation of overflow valve located on the fuel injection pump. See OVERFLOW VALVE under FUEL SYSTEMS in SYSTEM & COMPONENT TESTING - RAM PICKUP - DIESEL article. If overflow valve operates properly, go to next step. If overflow valve is defective, replace overflow valve. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 2. At this time, Fuel Pump Control Module (FPCM) is assumed to be defective and must be replaced. FPCM is incorporated into fuel injection pump and is non-serviceable. Replace fuel injection pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

DTC P0128: ENGINE IS COLD TOO LONG Monitor & Set Conditions Engine Coolant Temperature (ECT) sensor voltage is monitored when the engine is running, engine coolant temperature is 20 to 130°F (-6 to 55°C) and no ECT or battery temperature DTCs are set. DTC will set if coolant temperature reading is less than 170°F (77°C) after the engine has been running for 10-32 minutes (depending on engine coolant temperature at engine start). Possible Causes Wiring Harness ECT Sensor ECT Sensor - Engine Hot ECM Testing 1. Turn ignition off. Disconnect ECT sensor harness connector. The ECT sensor is located at the front of the cylinder head, near the thermostat housing. Inspect ECT sensor harness connector for miswired, corroded, pushed out or damaged terminals. If terminals are not miswired, corroded, pushed out or damaged, go to next step. If terminals are miswired, corroded, pushed out or damaged, repair as necessary. 2. This test procedure will be invalid if the thermostat is stuck open. Turn ignition on. Measure engine temperature near ECT sensor using an external temperature measuring device. Ensure engine temperature is less than 124°F (50°C). Using DRBIII(R) scan tool, monitor ECT sensor reading. If both temperature readings are within 10 percent of each other, go to next step. If both temperature readings are not within 10 percent of each other, replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 3. Continue monitoring engine temperature near ECT sensor using an external temperature measuring device and using a scan tool, continue monitoring ECT sensor reading. Start engine and allow it to reach a temperature greater than 180°F (82°C). If both temperature readings are within 10 percent of each other, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If both temperature readings are not within 10 percent of each other, replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If engine temperature does not reach 180°F (82° C), diagnose cooling system malfunction.

DTC P0125: COOLANT TEMP RATIONALITY Monitor & Set Conditions Engine Coolant Temperature (ECT) sensor voltage is monitored when the engine is running, engine coolant temperature is -40 to 150°F (-40 to 65°C) and no Intake Air Temperature (IAT), ECT or battery temperature DTCs are set. ECT sensor voltage is also monitored when the engine is off with ignition on. Intake Air Temperature (IAT) must be less than 80°F (26°C), battery voltage must be 8-16 volts and no IAT, ECT or battery temperature DTCs are set. When the engine is running, DTC will set if coolant temperature reading does not change greater than 6°F within 10 minutes of starting the engine. With the engine off and ignition on, DTC will set if coolant temperature reading is greater than 140°F (60°C). Possible Causes Wiring Harness ECT Sensor ECT Sensor - Engine Hot ECT Testing 1. Turn ignition off. Disconnect ECT sensor harness connector. The ECT sensor is located at the front of the cylinder head, near the thermostat housing. Inspect ECT sensor connector for miswired, corroded, pushed out or damaged terminals. If terminals are not miswired, corroded, pushed out or damaged, go to next step. If terminals are miswired, corroded, pushed out or damaged, repair as necessary. 2. This test procedure will be invalid if the thermostat is stuck open. Turn ignition on. Measure engine temperature near ECT sensor using an external temperature measuring device. Ensure engine temperature is less than 124°F (50°C). Using DRBIII(R) scan tool, monitor ECT sensor reading. If both temperature readings are within 10 percent of each other, go to next step. If both temperature readings are not within 10 percent of each other, replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 3. Continue monitoring engine temperature near ECT sensor using an external temperature measuring device and using a scan tool, continue monitoring ECT sensor reading. Start engine and allow it to reach a temperature greater than 180°F (82°C). If both temperature readings are within 10 percent of each other, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If both temperature readings are not within 10 percent of each other, replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If engine temperature does not reach 180°F (82° C), diagnose cooling system malfunction.

DTC P0123: APP SENSOR SIGNAL VOLTAGE TOO HIGH Monitor & Set Conditions Accelerator Pedal Position Sensor (APPS) voltage is monitored when the engine is running. DTC may be stored if a high voltage is detected on APPS signal circuit or high voltage is detected between Engine Control Module (ECM) and Powertrain Control Module (PCM). Possible Causes 5-volt Supply At APPS Shorted To Voltage (Engine Running) APPS 5-volt Supply Circuit Shorted To Voltage APPS Signal Circuit Shorted To Voltage (Engine Running) APPS Signal Circuit Shorted To Voltage APPS Return Circuit Open APPS Signal Circuit Open From APPS To ECM APPS 5-volt Supply Circuit Open PCM (APPS) Circuit Shorted To Voltage With The Engine Running PCM (APPS) Short To Voltage With Ignition Key On APPS Open Between PCM And ECM Open APPS Circuit Accelerator Pedal Position Sensor (APPS) Engine Control Module Testing 1. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for ECM and PCM DTCs. Determine if DTC is set by ECM or PCM. If DTC is set by ECM, go to next step. If DTC is not set by ECM, go to step 11. 2. Turn ignition off. Disconnect APPS sensor harness connector. APPS is located on a bracket, just above fuel injection pump. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, go to step 5. 3. Turn ignition off. Check for poor connection/terminal contact at APPS harness connector. Repair as necessary. Ensure APPS harness connector is still disconnected. Turn ignition on with engine off. Using DVOM, measure voltage between terminal No. 5 (Dark Blue/White wire) and terminal No. 4 (Black/Yellow wire) on APPS harness connector. If the voltage is 5.5 volts or less, go to next step. If the voltage is greater than 5.5 volts, repair short to voltage in Dark Blue/White wire. 4. Turn ignition off. Ensure APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for poor connection/terminal contact at ECM harness connector. Repair as necessary. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 5 (Dark Blue/White wire) on APPS connector. If the voltage is greater than 5.5 volts, repair short to voltage on Dark Blue/White wire between APPS and ECM. If the voltage is 5.5 volts or less, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 5. Check for poor connection/terminal contact at APPS harness connector. Repair as necessary. Ensure APPS connector is still disconnected. Start engine. Using a DVOM, measure voltage between cylinder block (ground) and terminal No. 3 (Light Blue/Black wire) on APPS connector. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, go to step 8. 6. Turn ignition off. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 3 (Light Blue/Black wire) on APPS connector. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, repair short to voltage on Light Blue/Black wire between APPS and ECM (short only exists when the engine is running). 7. Turn ignition off. Ensure APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for poor connection/terminal contact at ECM harness connector. Repair as necessary. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 3 (Light Blue/Black wire) on APPS connector. If the voltage is greater than 5.5 volts, repair short to voltage on Light Blue/Black wire between APPS and ECM (short only exists when the ignition is on). If the voltage is 5.5 volts or less, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 8. Turn ignition off. Ensure APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for poor connection/terminal contact at ECM harness connector. Repair as necessary. Check Black/Yellow wire for continuity between terminal No. 4 on APPS harness connector and terminal No. 32 on ECM harness connector. If continuity exists, go to next step. If continuity does not exist, repair open in Black/Yellow wire between APPS and ECM. 9. Ensure APPS harness connector and ECM harness connector are still disconnected. Check Light Blue/Black wire for continuity between terminal No. 3 on APPS harness connector and terminal No. 25 on ECM harness connector. If continuity exists, go to next step. If continuity does not exist, repair open in Light Blue/Black wire between APPS and ECM. 10. Ensure APPS harness connector and ECM harness connector are still disconnected. Check Dark Blue/White wire for continuity between terminal No. 5 on APPS harness connector and terminal No. 31 on ECM harness connector. If continuity exists, go to next step. If continuity does not exist, replace APPS. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 11. Turn ignition off. Disconnect PCM harness connectors. PCM is located at passenger's side rear corner of engine compartment. Check for poor connection/terminal contact at PCM harness connectors. Repair as necessary. Start engine and allow the engine to idle. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 23 (Orange/Dark Blue wire) on PCM harness connector C1. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, go to step 14. 12. Turn ignition off. Ensure PCM harness connectors are still disconnected. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 23 (Orange/Dark Blue wire) on PCM harness connector C1. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, repair short to voltage on Orange/Dark Blue wire between PCM and ECM (short only exists when the engine is running). 13. Turn ignition off. Ensure PCM harness connectors are still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50- pin connector. Check for poor connection/terminal contact at ECM harness connector. Repair as necessary. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 23 (Orange/Dark Blue wire) on PCM harness connector C1. If the voltage is greater than 5.5 volts, repair short to voltage on Orange/Dark Blue wire between PCM and ECM (short only exists when the ignition is on). If the voltage is 5.5 volts or less, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 14. Turn ignition off. Ensure PCM harness connectors are still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50- pin connector. Check for poor connection/terminal contact at PCM harness connectors. Repair as necessary. Check continuity of Orange/Dark Blue wire between terminal No. 23 on PCM harness connector C1 and terminal No. 28 on ECM harness connector. If continuity does not exist, repair open in Orange/Dark Blue wire between PCM and ECM. If continuity exists, the test is complete. Clear DTCs from both ECM and PCM. If you find that your APPS is bad you can replace it with a Timbo Apps from the Mopar1973man Store.

DTC P0122: APP SENSOR SIGNAL VOLTAGE TOO LOW Monitor & Set Conditions Accelerator Pedal Position Sensor (APPS) voltage is monitored when the engine is running. DTC may be stored if low voltage is detected on APPS signal circuit or low voltage is detected between Engine Control Module (ECM) and Powertrain Control Module (PCM). Possible Causes 5-volt Supply At APPS Shorted To ECM Sensor Ground APPS Signal Circuit Shorted To ECM Sensor Ground 5-volt Supply To Ground APPS Signal Circuit Shorted To Ground APPS Signal Circuit Open To ECM PCM (APPS) Short To ECM Sensor Ground ECM (APPS) To PCM (APPS) Circuit Shorted ECM (APPS) To PCM (APPS) Circuit Open Short To ECM Sensor Ground Accelerator Pedal Position Sensor (APPS) Engine Control Module Powertrain Control Module Testing 1. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for ECM and PCM DTCs. Determine if DTC is set by ECM or PCM. If DTC is set by ECM, go to next step. If DTC is not set by ECM, go to step 7. 2. Turn ignition off. Disconnect APPS sensor harness connector. APPS is located on the bracket, just above fuel injection pump. Turn ignition on with engine off. Using DVOM, measure voltage between cylinder block (ground) and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If the voltage is greater than 4.5 volts, go to next step. If the voltage is 4.5 volts or less, go to step 6. 3. Turn ignition off. Ensure APPS harness connector is still disconnected. Check for continuity between terminal No. 4 (Black/Yellow wire) and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If continuity does not exist, go to next step. If continuity exists, repair short between Dark Blue/White and Black/Yellow wires. The Black/Yellow wire is the sensor ground circuit. 4. Ensure APPS harness connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for continuity between terminal No. 4 (Black/Yellow wire) and terminal No. 3 (Light Blue/Black wire) on APPS harness connector. If continuity does not exist, go to next step. If continuity exists, repair short between Black/Yellow and Light Blue/Black wires. 5. Ensure APPS and ECM connectors are still disconnected. Check for continuity between ground and terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If continuity does not exist, go to next step. If continuity exists, repair short to ground in Dark Blue/White wire. 6. Turn ignition off. Ensure APPS connector is still disconnected. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check Dark Blue/White wire for continuity between terminal No. 5 on APPS harness connector and terminal No. 31 on ECM harness connector. If continuity does not exist, repair open in Dark Blue/White wire. If continuity exists, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 7. Turn ignition off. Disconnect PCM harness connectors. PCM is located at passenger's side rear corner of engine compartment. Check for continuity between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If continuity does not exist, go to step 9. If continuity exists, go to next step. 8. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for continuity between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If continuity does not exist, the test is complete. If continuity exists, repair short to ground in Orange/Dark Blue wire. 9. Ensure PCM harness connectors are still disconnected. Disconnect ECM connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for the circuit). If continuity does not exist, go to next step. If continuity exists, repair short to ground in Orange/Dark Blue wire. 10. Check Orange/Dark Blue wire for continuity between terminal No. 5 on APPS harness connector and terminal No. 31 on ECM harness connector. If continuity does not exist, repair open in Orange/Dark Blue wire. If continuity exists, go to next step. 11. Reconnect ECM harness connector. Ensure PCM harness connectors are still disconnected. Turn ignition on with engine off. Using DVOM, measure voltage between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If the voltage is greater than 0.4 volt, the test is complete. If the voltage is 0.4 volt or less, go to next step. 12. Turn ignition off. Disconnect APPS harness connector. Check for continuity between ground and terminal A23 (Orange/Dark Blue wire) on PCM harness connector (APPS circuit). If continuity does not exist, replace APPS. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If continuity exists, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If you find that your APPS is bad you can replace it with a Timbo Apps from the Mopar1973man Store.

DTC P0121: ACCEL POS SENSOR VOLTS DO NOT AGREE W/IDLE VALID SIGNAL Monitor & Set Conditions Accelerator Pedal Position Sensor (APPS) voltage is monitored with the throttle at less than 15 percent of full throttle for about one second or when the vehicle speed is greater than 10 MPH for about one second. DTC may be stored if the idle valid signal indicates an idle condition while APPS signal voltage does not indicate an idle condition or if the idle valid signal does not indicate an idle condition while APPS signal voltage indicates an idle condition. Possible Causes 5-volt Supply Circuit Shorted To Voltage With Ignition On APP Sensor Idle Valid Signal (IVS) #2 Circuit Shorted To Voltage Sensor Ground Circuit Open 5-volt Supply Circuit Shorted To Voltage With The Engine Running ECM Testing 1. Turn ignition off. Disconnect APPS harness connector. APPS is located on a bracket, just above fuel injection pump. Start engine and allow the engine to idle. Using DVOM, measure voltage at terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, go to step 3. 2. Turn ignition off. Turn ignition on with engine off. Using DVOM, measure voltage at terminal No. 5 (Dark Blue/White wire) on APPS harness connector. If the voltage is greater than 5 volts, repair short to voltage on Dark Blue/White wire between APPS and ECM when the ignition is on. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. If the voltage is 5 volts or less, repair short to voltage on Dark Blue/White wire between APPS and ECM when the engine is running. 3. Turn ignition off. Using DVOM, measure resistance between ground and terminal No. 4 (Black/Yellow wire) on APPS connector. If resistance is 10 ohms or greater, go to next step. If resistance is less than 10 ohms, replace APPS. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. 4. Start engine and allow the engine to idle. Turn ignition off. Turn ignition on with engine off. Using DVOM, measure voltage at terminal No. 2 (Light Green/Dark Blue wire) on APPS harness connector. If the voltage is 5.5 volts or less, go to next step. If the voltage is greater than 5.5 volts, repair short to voltage on Light Green/Dark Blue wire between APPS and ECM. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. 5. Turn ignition off. Disconnect ECM harness connector. ECM is located on driver's side of the engine, just in front of fuel transfer pump and contains a 50-pin connector. Using DVOM, measure the resistance of Black/Yellow wire between terminal No. 4 on APPS harness connector and terminal No. 32 on ECM connector. If resistance is 10 ohms or greater, repair open in Black/Yellow wire between APPS and ECM. If resistance is less than 10 ohms, replace and program the ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If you find that your APPS is bad you can replace it with a Timbo Apps from the Mopar1973man Store.