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Wiring Diagram:

Fig 1: Wiring Diagram - DTC P0604 Internal Control Module Random Access Memory (Ram) Error

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DTC P0604 DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1. CHECK FOR ANY OTHER DTC ON DISPLAY.	Is any other DTC displayed?	Check the relevant DTC using the List of Diagnostic Trouble Code (DTC). < Ref. to , LIST OF DIAGNOSTIC TROUBLE CODE (DTC) . >	A temporary poor contact occurs.