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P0606 - Powertrain Control Module Internal Communication Error

P0606 - POWERTRAIN CONTROL MODULE INTERNAL COMMUNICATION ERROR

Description:  P0606 indicates a register readback (PCM internal communications) error.
Possible Causes: 
  • PCM damaged or defective.
Diagnostic Aids:  Internal PCM failure. Replace the PCM. For Electronic Throttle Control applications, an internal PCM failure, or an ETC system FMEM condition exists. Repairing the other DTCs can fix the P0606.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Vehicles with electronic throttle control (ETC) DTC is an indication of a failure mode in the Electronic Throttle Control system, which includes the APPS, ETB, and PCM. It is accompanied by other DTCs which provide repair direction. Proceed to DIAGNOSTIC TROUBLE CODE (DTC) DESCRIPTION  table to repair those DTCs, and the P0606 will not be reset. DTC is an indication of a failure mode in the Electronic Throttle Control system, which includes the APPS, ETB, and PCM. It is accompanied by other DTCs which provide repair direction. Proceed to DIAGNOSTIC TROUBLE CODE (DTC) DESCRIPTION  table to repair those DTCs, and the P0606 will not be reset. DTC is an indication of a failure mode in the Electronic Throttle Control system, which includes the APPS, ETB, and PCM. It is accompanied by other DTCs which provide repair direction. Proceed to DIAGNOSTIC TROUBLE CODE (DTC) DESCRIPTION  table to repair those DTCs, and the P0606 will not be reset.
All Others Be sure to check for aftermarket performance products before replacing the PCM. If replacement is necessary, refer to DIAGNOSTIC METHODS - CNG, FLEXFUEL & GASOLINE Be sure to check for aftermarket performance products before replacing the PCM. If replacement is necessary, refer to DIAGNOSTIC METHODS - CNG, FLEXFUEL & GASOLINE Be sure to check for aftermarket performance products before replacing the PCM. If replacement is necessary, refer to DIAGNOSTIC METHODS - CNG, FLEXFUEL & GASOLINE