P0625
P0625-GENERATOR FIELD CONTROL CIRCUIT LOW
- When Monitored:
With the engine running and battery voltage greater than 10.4 volts.
- Set Condition:
The PCM detects that the generator field control is shorted low.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Pre-Diagnostic Troubleshooting Procedure
1. DTC IS ACTIVE
1. Start the engine and allow it to reach normal operating temperature.
WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
2. With the scan tool, select View DTCs.
Is the status Active for this DTC?
Yes
- Go to 2
No
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking for an Intermittent DTC
2. (K20) GEN FIELD CONTROL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Generator connector.
3. Disconnect the Powertrain Control Module (PCM) connector.
4. Measure the resistance between ground and the (K20) Gen Field Control circuit in the Generator harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the (K20) Gen Field Control circuit for a short to ground.
- Perform the PCM Verification TestPCM Verification Test.
No
- Go to 3
3. (K20) GEN FIELD CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.
1. Measure the resistance of the (K20) Gen Field Control circuit between the Generator harness connector and the Powertrain Control Module (PCM) harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go to 4
No
- Repair the (K20) Gen Field Control circuit for an open circuit or high resistance.
- Perform the PCM Verification TestPCM Verification Test.
4. GENERATOR FIELD CONTROL ACTUATION
1. Connect the Powertrain Control Module (PCM) connector.
2. Turn the ignition on.
3. With the scan tool, actuate the Generator field control to the ON (100%) position.
4. Using a 12 volt test light connected to ground, check the (K20) Gen Field Control circuit in the Generator harness connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
5. With the scan tool, actuate the Generator field control to the OFF (0%) position.
6. Using a 12 volt test light connected to ground, check the (K20) Gen Field Control circuit in the Generator harness connector.
NOTE: The test light should not be illuminated.
Is the test light illuminated and bright with the actuation ON (100%) and not illuminated with the actuation OFF (0%)?
Yes
- Go to 5
No
- Go to 6
5. GENERATOR
1. Turn the ignition off.
2. Inspect the wiring and connectors between the Generator and the Powertrain Control Module (PCM).
3. Look for any chafed, pierced, pinched, or partially broken wires.
4. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM Verification TestPCM Verification Test.
No
- Replace the Generator.
- Perform the PCM Verification TestPCM Verification Test.
6. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Generator and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Search for any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM Verification TestPCM Verification Test.
No
- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification TestPCM Verification Test.