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DTC P0604

DTC P0604  PCM random access memory (RAM) error 
DETECTION CONDITION 
  • The PCM internal RAM malfunction.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • PCM internal RAM malfunction
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA (Mode 12) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) 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.
No Go to the next step.
3 VERIFY TROUBLESHOOTING OF DTC P0604 COMPLETED 
  • Clear the DTC from the PCM memory using the M-MDS.
  • Perform the KOEO or 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.
4 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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