Common Symptoms
- Check engine light illuminated
- Engine may not start or starts and immediately stalls
- Transmission may not shift properly or stuck in limp mode
- Various warning lights illuminated on instrument cluster
- Engine runs rough or with poor performance
- Loss of communication with scan tool or intermittent scan tool connection
Most Likely Root Causes
- Corrupted or incomplete ECM/PCM software programming
- Low battery voltage during module programming or reflash procedure
- Interrupted power supply during software update
- Failed or failing engine control module
- Incorrect software version installed for vehicle application
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Component Location
The engine control module is typically located in the engine compartment, often mounted on the firewall, inner fender, or under the intake manifold.
Manufacturer Notes
Some manufacturers require specific initialization or relearn procedures after control module reprogramming to clear this fault code.
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