P2146: Fuel injector group A supply voltage circuit or open

What P2146 means

On many engines, especially direct injection diesels, the ECU powers the injectors in groups. This code means the supply circuit for group A does not have the correct voltage or is open. Which injectors make up group A is up to each manufacturer. If those injectors stop working, the engine loses cylinders.

Most common causes

• A loose, dirty or corroded connector on one of the injectors in the group
• An injector supply wire broken, chafed or shorted
• An injector in the group with a shorted coil dragging the whole line down
• A loose or damp ECU connector
• A failed output stage in the ECU, which may need repair or replacement

Symptoms

• Engine warning light on
• The engine shakes or runs on fewer cylinders
• Big loss of power or limp mode
• Hard starting or no start

Can you drive with P2146?

Better not With a group of injectors unpowered the engine runs badly, may cut out, and unburnt fuel can damage the catalyst. Only drive if you must, straight to a garage.

How to check it

Note whether misfire codes for specific cylinders are also stored (P0301, P0302 and so on): they show which injectors belong to the affected group and where to look first.

How to read and clear P2146 with Final OBD

Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P2146 with this same explanation and whether it’s confirmed, pending or permanent.

With Free you read this code with its short description for nothing, and clear it if the engine stores it over standard OBD. With Pro you get the full explanation, how the car was running when it was logged (revs, temperature, load) and clearing in every control unit.

Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.

Similar codes

• P2127 Throttle or pedal position sensor E circuit low
• P2128 Throttle or pedal position sensor E circuit high
• P2135 Throttle or pedal position sensors A and B voltage mismatch
• P2138 Throttle or pedal position sensors D and E voltage mismatch
• P2177 System too lean off idle (bank 1)
• P2178 Mixture too rich away from idle (bank 1)
• P2179 Mixture too lean away from idle (bank 2)
• P2187 Mixture too lean at idle (bank 1)
• P2100 Throttle actuator A control motor circuit open
• P2101 Throttle actuator A control motor circuit range or performance
• P2102 Throttle actuator A control motor circuit low
• P2104 Throttle control system: forced idle

P2146 is a generic code, so it means the same on any make, for example on Citroën, Hyundai, Mercedes-Benz, Mini, Renault, Volvo. See what Final OBD does on your car in makes and models.