P0605 Lack of proper voltage and/or ground to the PCM, Defective PCM ROM memory module, Defective PCM ground circuit(s), Defective PCM controlled output devices and how to solve the problem
Check the battery voltage and charging system to ensure they are functioning properly.
Inspect the wiring and connections between the PCM and battery/charging system to ensure there are no loose or damaged connections.
Check the ground circuits between the PCM and vehicle chassis to ensure there are no loose or damaged connections.
Inspect the PCM controlled output devices, such as solenoids and actuators, to ensure they are functioning properly and not shorted.
Check the ROM memory module of the PCM to ensure it is not defective.
If necessary, replace the PCM with a new one that matches the vehicle's specifications.
Clear the trouble code and perform a road test to ensure the issue has been resolved.
