P20CD — Exhaust Aftertreatment Fuel Injector A Control Circuit Low
Exhaust Aftertreatment Fuel Injector A Control Circuit Low: the control-circuit voltage is below the expected range. This injector doses fuel into the exhaust to raise temperature for diesel particulate-filter regeneration; it does not fuel the engine.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Aftertreatment fuel injector
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Short to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Possible symptoms
- Check engine light on
- Misfire or rough idle on the affected cylinder
- Increased fuel consumption
- Possible fuel smell or smoke from exhaust
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
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.