Technical Definition:

(Internal Control Module) Read-Only Memory (ROM) Error

Technical Description:

This trouble code basically means that the PCM/ECM (powertrain/engine control module) has detected an internal control module fault in the ROM (read only memory) in the PCM. The PCM is basically the vehicle’s “electronic brain” that controls functions such as fuel injection, ignition, etc. When self-checks fail in the ROM, this DTC is set.

Possible Causes:

• There is an internal fault in the PCM / ECM
• Using an aftermarket performance programmer may trigger this code

Possible Symptoms:

Symptoms of a P0605 DTC will include MIL (malfunction indicator lamp) illumination, although there may be other symptoms including but not limited to various warning lights on dash, stalling, and no start conditions.

Control Module Fault

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Engine Control Module (ECM) may be faulty
– ECM harness power supply circuit is open or shorted
– ECM harness ground circuit is open or shorted

Specific Makes:

– Engine may not start