DTC P2503

DTC P2503	Charging system voltage low input
DETECTION CONDITION	The PCM needs more than 19.5 A from the generator, and judges the generator output voltage to be below 8.5 V during the engine running. Diagnostic support note This is a continuous monitor (other). The MIL does not illuminate. FREEZE FRAME DATA (Mode 2/Mode 12) is available. The DTC is stored in the PCM memory.
POSSIBLE CAUSE	Drive belt exceed limit Generator connector or terminals malfunction Short to ground in wiring harness between generator terminal D and PCM terminal 2AI Short to ground in wiring harness between generator terminal P and PCM terminal 2AJ PCM connector or terminals malfunction Open circuit in wiring harness between generator terminal D and PCM terminal 2AI Open circuit in wiring harness between generator terminal P and PCM terminal 2AJ Generator malfunction PCM malfunction

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 12) AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED Have the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS (other related) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2	VERIFY RELATED SERVICE BULLETINS AVAILABILITY Verify related Service Bulletins availability. Is any related Service Bulletins available?	Yes	Perform the repair or diagnosis according to the available Service Bulletins. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT DRIVE BELT CONDITION Verify that the drive belt auto tensioner indicator mark does not exceed limit. Is there any malfunction?	Yes	Replace the drive belt, then go to Step 9. (See DRIVE BELT REPLACEMENT ).
3		No	Go to the next step.
4	INSPECT GENERATOR CONNECTOR AND TERMINALS Turn the ignition switch off. Disconnect the generator connector. Inspect for poor connection (such as damaged/pulled-out pins, corrosion). Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 9.
4		No	Go to the next step.
5	INSPECT GENERATOR CIRCUITS FOR SHORT TO GROUND Generator connector is disconnected. Inspect for continuity between the following terminals (wiring harness-side) and body ground: Generator terminal D Generator terminal P 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 PCM internal circuit). (See PCM REMOVAL/INSTALLATION ). Go to Step 9.
5		No	Go to the next step.
6	INSPECT PCM CONNECTOR AND TERMINALS Disconnect the PCM connector. Inspect for poor connection (such as damaged/pulled-out pins, and corrosion). Is there any malfunction?	Yes	Repair or replace the connector or terminals, then go to Step 9.
6		No	Go to the next step.
7	INSPECT GENERATOR CIRCUITS FOR OPEN CIRCUIT Generator and PCM connectors are disconnected. Inspect for continuity between the following terminals (wiring harness-side): Generator terminal D and PCM terminal 2AI Generator terminal P and PCM terminal 2AJ Is there continuity?	Yes	Go to the next step.
7		No	Repair or replace the wiring harness for a possible open circuit, then go to Step 9.
8	INSPECT GENERATOR Inspect the generator. (See GENERATOR INSPECTION [LF] .) Is there any malfunction?	Yes	Replace the generator, then go to the next step. (See GENERATOR REMOVAL/INSTALLATION [LF] ).
8		No	Go to the next step.
9	VERIFY TROUBLESHOOTING OF DTC P2503 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. 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 ).
9		No	Go to the next step.
10	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 ).
10		No	DTC troubleshooting completed.