Internal Control Module Read Only Memory (ROM) Error
Common Symptoms
- Check Engine Light or Malfunction Indicator Lamp illuminated
- Engine may not start or cranks but fails to run
- Intermittent stalling or engine dying unexpectedly
- Loss of communication with scan tool or inability to read codes
- Erratic engine performance or drivability issues
- Multiple unrelated fault codes stored simultaneously
Most Likely Root Causes
- Failed or failing engine control module (ECM/PCM)
- Corrupted software or firmware in the control module
- Voltage spike or electrical surge damage to ECM/PCM
- Water intrusion or corrosion inside the control module
- Poor ground connection to the control module
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Component Location
The engine control module is typically mounted in the engine bay on the firewall, inner fender, or under the dashboard on the driver side.
Manufacturer Notes
This code indicates internal processor or memory failure and typically requires ECM/PCM replacement or reprogramming after verifying power and ground integrity.
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