P0294 fault code: Cylinder 12 Injector Circuit Low

Can I drive with P0294? — Limit driving

Limit driving with P0294. Low injector-circuit on cylinder 12 needs a workshop. Stop if the lamp flashes or the engine judders badly.

P0294 means “Cylinder 12 Injector Circuit Low” — a fuel and injector circuits fault in the powertrain. Limit driving. Cylinder 12 injector circuit low means the driver for that cylinder is not seeing a normal current. Leave the injector fitted until a technician depressurises the system.

Can I DIY?

Do not DIY this repair. We do not publish DIY repair or strip-down steps for this code on this page. Read codes and observe only; leave the repair to a qualified garage.

Do not DIY this repairDIY boundary
ToolsSpecialist tools or workshop equipment — typically a professional garage job.

This fault is in the professional-only category. We do not publish strip-down or fitting steps on this page. Use a qualified garage.

Hot systems

Never open a hot coolant cap — pressure can scald you. Exhaust and catalytic converter get hot enough to burn and ignite debris. Stay clear of electric fans; they can run after shut-off.

P02xxFuel and injector circuits
MOT fail riskif the warning light stays on

What does P0294 mean?

P0294 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P02xx block, which covers fuel and injector circuits. The stored description is “Cylinder 12 Injector Circuit Low”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0294 fail an MOT?

An illuminated engine management light is a Major defect at MOT (automatic fail) until the fault is repaired and the light stays off.

Before booking your test, check what usually fails on your car: see our MOT pass rates by make and model, built from 33.1 million DVSA tests.

What the MOT data says

No MOT certificate item corresponds to this code; MOT outcome data cannot be shown.

Related guides

P0294 — quick answers

Is it safe to drive with P0294?

Limit driving. Limit driving with P0294. Low injector-circuit on cylinder 12 needs a workshop. Stop if the lamp flashes or the engine judders badly.

Can I fix P0294 myself?

Do not DIY this repair. We do not publish DIY repair or strip-down steps for this code on this page. Read codes and observe only; leave the repair to a qualified garage. Specialist tools or workshop equipment — typically a professional garage job.

Will P0294 fail my MOT?

An illuminated engine management light is a Major defect at MOT (automatic fail) until the fault is repaired and the light stays off.

Fault-code identifiers are standard diagnostic facts. Their explanations and diagnostic guidance on this site are original editorial summaries, not reproduced SAE wording. MOT defect rules reflect the DVSA MOT inspection manual (2026). This page is general guidance for UK drivers, not a substitute for a professional diagnosis.