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DTC P2502

DTC P2502 Charging system voltage problem
DETECTION CONDITION 
  • The PCM monitors the generator output voltage and the battery voltage when the engine is running. If the generator output voltage is more than 16.9 V and the battery voltage is less than 10.9 V  , the PCM determines that there is a charging system voltage malfunction.

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 or open circuit in generator power supply circuit
    • Short to ground in wiring harness between battery positive terminal and generator terminal 2A
    • MAIN 120 A fuse malfunction
    • Open circuit in wiring harness between battery positive terminal and generator terminal 2A
  • Generator malfunction
  • Battery positive terminal poor installation
  • Battery malfunction
  • PCM malfunction
G07878161
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.
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.
No Go to the next step.
3 INSPECT BATTERY CHARGING CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • Generator connector is disconnected.
  • Measure the voltage between generator terminal 2A (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Inspect the MAIN 120 A fuse.
  • If the fuse is melt:
    • Repair or replace the wiring harness for a possible short to ground.
    • Replace the fuse.
  • If the fuse is deterioration:
    • Replace the fuse.
  • If the fuse is normal:
    • Repair or replace the wiring harness for a possible open circuit.

Go to Step 7.
4 INSPECT GENERATOR 
 Yes Replace the generator, then go to Step 7.
(See GENERATOR REMOVAL/INSTALLATION [13B-MSP] ).
No Go to the next step.
5 INSPECT BATTERY POSITIVE TERMINAL FOR POOR INSTALLATION 
  • Turn the ignition switch off.
  • Inspect for looseness of the battery positive terminal.
  • Is there any malfunction?
 Yes Connect the battery positive terminal correctly, then go to Step 7.
No Go to the next step.
6 INSPECT BATTERY 
 Yes Replace the battery, then go to the next step.
(See BATTERY REMOVAL/INSTALLATION [13B-MSP] ).
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P2502 COMPLETED 
  • Mate sure to reconnect ail 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
No Go to the next step.
8 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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