This code indicates that the Powertrain Control Module (PCM) has detected an error in its internal memory (ROM). The ROM stores the program instructions that the PCM uses to operate the engine and transmission. If the ROM is damaged or corrupted, the PCM will not be able to function properly and the vehicle may experience a variety of problems, including:
- Engine stalls or hesitates
- Transmission shifts erratically
- Check Engine Light illuminates
- Reduced fuel economy
- Poor performance
To diagnose a P0601 code, a mechanic will typically use a scan tool to retrieve the trouble code from the PCM. The mechanic will then inspect the PCM for any signs of damage, such as cracks or corrosion. If the PCM is damaged, it will need to be replaced.
If the PCM is not damaged, the mechanic will then perform a series of tests to check the integrity of the ROM. If the ROM is corrupted, the mechanic will need to reprogram the PCM.
Reprogramming the PCM involves uploading a new copy of the program instructions to the PCM. This can be done using a scan tool or a special programming tool. Once the PCM has been reprogrammed, the mechanic will clear the trouble code and retest the vehicle to make sure the problem is resolved.
