OBD-II Generic Error Code P2155: How to Fix It

Q: Can I drive my car with a P2155 code?

Short distances may be possible if the vehicle is running smoothly, but it is not recommended. A P2155 fault means one or more fuel injectors in group D may not be receiving proper voltage, which can cause engine misfires. Sustained misfiring can overheat and permanently damage your catalytic converter, which is a very expensive repair. Get the fault diagnosed as soon as possible.

Q: What causes the P2155 code?

The most common causes include damaged or corroded wiring in the fuel injector group D harness, a blown injector fuse, a faulty injector relay, poor electrical connections at the injector connectors, failed fuel injectors (open or shorted coil), or — less commonly — a faulty engine control module (ECM) that is not supplying the correct voltage to the injector circuit.

Q: How much does it cost to fix a P2155 code?

Repair cost depends entirely on the root cause. A blown fuse costs less than $5 to fix yourself. A faulty relay typically costs $10–$30. Wiring harness repair at a shop can range from $100–$400 depending on severity. Replacing one or more fuel injectors can cost $150–$600 per injector at a shop including labor. ECM replacement or reprogramming is the most expensive option, ranging from $500 to over $1,500 depending on the vehicle.

Q: Which cylinders are in fuel injector group D?

Group D refers to a manufacturer-defined set of cylinders sharing a common injector power supply circuit. On many V8 engines it corresponds to the rear bank injectors (cylinders 5–8), but the exact assignment varies by make, model, and year. Always consult your vehicle's specific factory service manual or wiring diagram to confirm which cylinders belong to group D on your engine.

Q: Will a bad fuel injector trigger a P2155 code?

Yes, a fuel injector with an internally shorted coil can pull down the supply voltage for the entire group D circuit, triggering P2155. However, individual injector failures more commonly trigger injector-specific codes like P0201–P020X. P2155 specifically points to the supply voltage circuit, so wiring, fuses, and relays should be checked before condemning individual injectors.

Abstract

The P2155 code indicates a problem with the supply voltage circuit for fuel injector group D — the circuit that delivers power to a specific bank of fuel injectors in your engine. This fault can result in rough idling, misfires, poor fuel economy, or even a no-start condition because the affected injectors may not be firing correctly. While this is a medium-severity code, it should be addressed promptly to avoid catalytic converter damage or further engine problems.