P2156 — Fuel Injector Group D Supply Voltage Circuit Low
The supply voltage feeding injector group D has dropped below the lower limit. The injectors in this group lose drive voltage and may stop firing, so the cylinders they serve run lean or cut out. Causes: a blown fuse, a failed injector supply relay, a voltage drop in the supply harness, or a poor ground or connector on the group-D supply.
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
- Fuel injector group d
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Fuse, relay, or wiring fault on supply
- 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.