P1603
DTC P1603: CAN Communication Data ErrorDTC Detecting Condition
When abnormality on the idle speed control signal, the engine power control signal or so on outputted from TCM is detected by ECM, ECM sets DTC P1603. (TCM outputs the trouble code to ECM when TCM cannot compute the engine control signal due to malfunctions of sensor circuits used for gear shift control.)
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DTC Troubleshooting