P2503
P2503-CHARGING SYSTEM OUTPUT LOW
For a complete wiring diagram Refer to the Wiring Information.
- When Monitored:
The engine running. The engine RPM is high enough to assure sufficient generator current output to satisfy the electrical loads.
- Set Condition:
The battery sensed voltage is less than the target charging voltage, during engine operation, for a calibrateable amount of time. One Trip Fault. Generator light will illuminate.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. ACTIVE DTC
NOTE: Inspect the vehicle for aftermarket accessories that may exceed the Generator System output.
NOTE: The battery must be fully charged.
NOTE: The Generator belt tension and condition must be checked before continuing.
1. Ignition on, engine not running.
2. With a scan tool, select View DTCs.
3. Read and record the related Freeze Frame data for P2503.
4. With a scan tool, erase DTCs.
5. Start the engine.
6. Allow the idle to stabilize.
7. Ignition on, engine not running.
8. With the scan tool, select View DTCs.
Is the DTC Active at this time?
Yes
- Go To 2
No
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition Test.
2. FUSED B+ CIRCUIT HIGH RESISTANCE
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 can result in possible serious or fatal injury.
1. Ignition on, engine not running.
2. Measure the voltage between the Generator B+ Output Terminal and the Battery + Post.
3. Start the engine.
Is the voltage above 0.4 of a volt?
Yes
- Repair the excessive resistance in the battery positive circuit between the Generator and Battery.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 3
3. GENERATOR OPERATION
1. Turn the ignition off.
2. Disconnect the Generator Field harness connector.
3. Using a 12-volt test light connected to ground, probe (K125) Generator Field Control circuit in the Generator Field harness connector.
NOTE: The DTC needs to be cleared before actuating the Solenoid, if the DTC is not cleared, the Solenoid may not be allowed to actuate.
4. Ignition on, engine not running.
5. With a scan tool, actuate the Generator Field Driver.
NOTE: The test light should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows 100% actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 25% actuation, the brightness should be 25% as bright as a direct connection to the battery.
Does the test light illuminate accordingly?
Yes
- Verify that there is good pin to terminal contact in the Generator and the Powertrain Control Module connectors. If OK, replace the Generator.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 4
4. 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. Verify that there is good pin to terminal contact in the Generator and the Powertrain Control Module connectors.
4. Search for any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.