Possible Causes of P0601 (Internal PCM Failure):
* Internal PCM Hardware Failure: This is the most likely cause. A component within the PCM itself might be failing, causing intermittent or complete malfunction. This often requires PCM replacement.
* Low Voltage: Insufficient power supply to the PCM can cause internal errors. Check your battery voltage and alternator output. Poor wiring connections to the PCM can also contribute.
* Corrosion or Water Damage: Corrosion in the PCM connectors or water ingress into the PCM housing can cause internal shorts or damage to the circuitry.
* Software Glitch (Less Likely): In rare cases, a software glitch could trigger this code, although this is less probable than hardware failure in a car this age. A professional scan tool might be able to check the PCM's software for issues.
What NOT to Do:
* Don't keep resetting the code. This won't fix the problem and could lead to more severe engine damage.
What to Do:
1. Have it professionally diagnosed: Take your Prowler to a qualified mechanic or an auto parts store with diagnostic capabilities. They can use a scan tool to read more detailed information from the PCM and possibly pinpoint the exact problem within the PCM (if it's a hardware failure, a precise location within the module might not be possible).
2. Check the basics first (before going to the shop): Ensure your battery is properly charged and that the alternator is functioning correctly. Check all the wiring connections to the PCM, looking for corrosion, loose connections, or damage.
3. Consider PCM replacement (likely): If the diagnosis points to a PCM problem, you will likely need a replacement PCM. Make sure the replacement PCM is programmed correctly for your specific vehicle. This usually requires a professional scan tool.
Important Note: A faulty PCM can lead to significant drivability issues and potentially cause further engine damage if left unaddressed. It's crucial to get this resolved promptly.
