Regeneration Control Switch Circuit Low
Regeneration control switch input reads stuck low — short to ground or stuck-closed contact. The ECM may see a constant regen request which it cannot service while the vehicle is moving.
Affected components
- Regen request switch
Common causes
- High likelihood: Switch wire shorted to ground
- Low likelihood: Connector pins corroded - high contact resistance
- Low likelihood: Harness chafing through insulation
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.