DTC P1683: SPEED CONTROL POWER RELAY OR SPEED CONTROL 12V DRIVER CIRCUIT
1. Ensure ignition is off. Disconnect speed control servo connector. Speed control servo is located below driver's side battery tray. See Fig. 59 .
2. Turn ignition on with engine off. Using scan tool, actuate speed control servo. Using 12-volt test light, check for voltage at terminal No. 3 (Dark Blue/Red wire) on speed control servo connector. DO NOT depress brake pedal when checking voltage. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, go to step 8 .
3. Turn ignition off. Ensure speed control servo connector is still disconnected. Using ohmmeter, check resistance between ground and terminal No. 4 (Black wire) on speed control servo connector. DO NOT depress brake pedal when checking resistance. If resistance less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open on Black wire between speed control servo and ground connection. Ground connection is located on driver's side fender panel, just below speed control servo. Perform TEST VER-4A .
4. Ensure ignition is off and speed control servo connector is still disconnected. Disconnect PCM connectors. PCM is located at passenger's side rear corner of engine compartment. Using ohmmeter, check resistance between terminal No. 1 (Tan/Red wire) on speed control servo connector and terminal No. 4 (Tan/Red wire) on PCM connector C3. If resistance is less than 5 ohms, go to next step. If resistance 5 ohms or more, repair open on Tan/Red wire between speed control servo and PCM. Perform TEST VER-4A .
5. Ensure speed control servo connector and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and terminal No. 1 (Tan/Red wire) on speed control servo connector. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground on Tan/Red wire between speed control servo and PCM. Perform TEST VER-4A .
6. Ensure speed control servo connector and PCM connectors are still disconnected. Using ohmmeter, check No. 5 (Light Green/Red wire) on PCM connector C3. If resistance is less than 5 ohms, go to next step. If resistance 5 ohms or more, repair open on Light Green/Red wire between speed control servo and PCM. Perform TEST VER-4A .
7. Ensure speed control servo connector and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and terminal No. 2 (Light Green/Red wire) on speed control servo connector. If resistance is 5 ohms or more, replace speed control servo. Perform TEST VER-4A . If resistance is less than 5 ohms, repair short to ground on Light Green/Red wire between speed control servo and PCM. Perform TEST VER-4A .
8. Turn ignition off. Disconnect brake switch connector. Start engine and allow engine to idle. Place speed control switch in ON position. Shut engine off. Turn ignition on with engine off. Using scan tool, actuate speed control servo. Using 12-volt test light, check for voltage at terminal No. 3 (Dark Blue/Red wire) on speed control servo connector. DO NOT depress brake pedal when checking for voltage. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, go to step 12 .
9. Brake switch adjustment should be checked. Reinstall brake switch connector. To check brake switch adjustment, depress brake pedal. Ensure brakelights come on. Release brake pedal. Ensure brakelights go off. If brake switch is properly adjusted and brakelight operation is as specified, go to next step. If and brakelight operation is not as specified, replace brake switch, as brake switch is nonadjustable and can only be adjusted when NEW brake switch is installed. Perform TEST VER-4A .
10. Ensure ignition is off and speed control servo connector is still disconnected. Using ohmmeter, check resistance between ground and terminal No. 3 (Dark Blue/Red wire) on speed control servo connector. If resistance 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground on Dark Blue/Red wire between speed control servo and brake switch. Perform TEST VER-4A .
11. Disconnect brake switch connector. Using ohmmeter, check resistance between terminal No. 4 (Dark Blue/Red wire) on brake switch connector and terminal No. 3 (Dark Blue/Red wire) on speed control servo connector. If resistance is less than 5 ohms, replace brake switch. Perform TEST VER-4A . If resistance 5 ohms or more, repair open on Dark Blue/Red wire between brake switch and speed control servo. Perform TEST VER-4A .
12. Ensure ignition is off and speed control servo connector is still disconnected. Using ohmmeter, check resistance between ground and terminal No. 3 (Dark Blue/Red wire) on speed control servo connector. If resistance 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground on Dark Blue/Red wire between speed control servo and brake switch. Perform TEST VER-4A .
13. Ensure ignition is off and speed control servo connector is still disconnected. Disconnect PCM connectors. PCM is located at passenger's side rear corner of engine compartment. Using ohmmeter, check resistance between terminal No. 3 (Yellow/Red wire) on brake switch connector and terminal No. 11 (Yellow/Red wire) on PCM connector C3. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-4A . If resistance 5 ohms or more, repair open on Yellow/Red wire between brake switch and PCM. Perform TEST VER-4A .