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DTC P2503

DTC P2503

Charging system voltage low

DETECTION CONDITION

The PCM monitors the generator output voltage when the engine is running. If the generator output voltage is less than 8.5 V while the PCM needs more than 19.5 A from the generator, the PCM determines that the charging system voltage is low.

Diagnostic support note

This is a continuous monitor (other).
The MIL does not illuminate.
FREEZE FRAME DATA (Mode 2/Mode 12) is not available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

Generator connector or terminals malfunction
Short to ground in wiring harness between generator terminal 1A and PCM terminal 2AJ
Short to ground in wiring harness between generator terminal 1B and PCM terminal 2AI
Generator malfunction
PCM connector or terminals malfunction
Open circuit in wiring harness between generator terminal 1A and PCM terminal 2AJ
Open circuit in wiring harness between generator terminal 1B and PCM terminal 2AI
PCM malfunction

G07878162

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Verify related Service Bulletins and/or on-line repair information availability. Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
1		No	Go to the next step.
2	INSPECT GENERATOR CONNECTOR FOR POOR CONNECTION Turn the ignition switch off. Disconnect the generator connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 7.
2		No	Go to the next step.
3	INSPECT GENERATOR CIRCUIT FOR SHORT TO GROUND Generator connector is disconnected. Turn the ignition switch off. Inspect for continuity between the following circuits: Generator terminal 1A (wiring harness-side) and body ground Generator terminal 1B (wiring harness-side) and body ground Is there continuity?	Yes	If the short to ground circuit could be detected: Repair or replace the wiring harness for a possible short to ground. If the short to ground circuit could not be detected: Replace the PCM (short to ground in the PCM internal circuit). (See PCM REMOVAL/INSTALLATION Go to Step 7.
3		No	Go to the next step.
4	INSPECT GENERATOR Inspect the generator. (See GENERATOR INSPECTION [13B-MSP] ). Is there any malfunction?	Yes	Replace the generator, then go to Step 7. (See GENERATOR REMOVAL/INSTALLATION [13B-MSP] ).
4		No	Go to the next step.
5	INSPECT PCM CONNECTOR FOR POOR CONNECTION Turn the ignition switch off. Disconnect the PCM connector. Inspect for poor connection (such as damaged/pulled-out pins, corrosion). Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 7.
5		No	Go to the next step.
6	INSPECT GENERATOR CIRCUIT FOR OPEN CIRCUIT Generator and PCM connectors are disconnected. Turn the ignition switch off. Inspect for continuity between the following circuits: Generator terminal 1A (wiring harness-side) and PCM terminal 2AJ (wiring harness-side) Generator terminal 1B (wiring harness-side) and PCM terminal 2AI (wiring harness-side) Is there continuity?	Yes	Go to the next step.
6		No	Repair or replace the wiring harness for a possible open circuit, then go to the next step.
7	VERIFY TROUBLESHOOTING OF DTC P2503 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE ). Perform the KOER self test. (See KOEO/KOER SELF TEST ). Is the same DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION
7		No	Go to the next step.
8	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE ". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
8		No	DTC troubleshooting completed.