DTC P0563: CHARGING SYSTEM VOLTAGE TOO HIGH
Monitor & Set Conditions
Charging system voltage is monitored when ignition is on. DTC may be stored if battery supply voltage (B+ circuit) at Engine Control Module (ECM) is greater than 17 volts.
- DTC Present In The PCM
- ECM Ground Circuit(s) Open
- High Voltage At ECM - Engine Off
- High Voltage At ECM - Engine Running
1. Start engine and allow engine to idle. Using DVOM and Probe (6801), backprobe terminals No. 48 and 50 (Red/White wires) on ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. If voltage is less than 17 volts at both terminals, go to next step. If voltage is 17 volts or greater on either B+ circuit, perform CHARGING SYSTEM test under MISCELLANEOUS CONTROLS in SYSTEM & COMPONENT TESTING - RAM PICKUP - DIESEL article.
2. Shut engine off. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for PCM DTCs. If DTC P1594 does not exist in Powertrain Control Module (PCM), go to next step. If DTC P1594 exists in PCM, perform DTC P1594: CHARGING SYSTEM VOLTAGE TOO HIGH in appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
3. Turn ignition off. Using DVOM and probe, backprobe terminals No. 48 and 50 (Red/White wires) on ECM harness connector. If voltage is less than 17 volts at both terminals, go to next step. If voltage is 17 volts or greater on either B+ circuit, check for correct battery installation.
4. Disconnect ECM harness connector. Connect a test light between battery voltage and terminals No. 30 and 49 (Black/Tan wires) on ECM harness connector. These are the ECM ground circuits. If test light illuminates brightly at both terminals, test is complete. If test light does not illuminate brightly at either terminal, repair open or high resistance on Black/Tan wire between ECM and ground connection. Ground connection is located at ground connection for negative battery terminal.