P0071 fault code: Ambient Air Temperature Sensor Range/Performance

P0071 means “Ambient Air Temperature Sensor Range/Performance” — a fuel and air metering fault in the powertrain.

Can I DIY?

Professional-only boundary. Compare the displayed outside temperature only; do not spray or swap the sensor.

Do not DIYReviewed page boundary
ToolsSpecialist equipment

This is the conservative boundary from the reviewed code record. This page has no frozen site-wide safety grade, so it does not publish a repair route.

What to tell the garage about P0071

Do not drive. The ambient air temperature reading looks implausible next to other temperature inputs or how long the car has been parked, so the computer rejects it as out of range rather than a simple open or short.

Take these reviewed, code-specific details with you. They help the garage confirm the fault without turning this page into a repair procedure.

  • Ambient Air Temperature Sensor Range/Performance: Registration number
  • Ambient Air Temperature Sensor Range/Performance: Exact code P0071 and any companion codes
  • Ambient Air Temperature Sensor Range/Performance: Whether the engine management light is steady or flashing
  • Ambient Air Temperature Sensor Range/Performance: Parked outdoor temperature versus what the car displayed
P00xxFuel and air metering
MOT fail riskif the warning light stays on

What does P0071 mean?

P0071 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P00xx block, which covers fuel and air metering. The stored description is “Ambient Air Temperature Sensor Range/Performance”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0071 fail an MOT?

MOT requires the engine malfunction indicator lamp to be off. P0071 does not create a separate ambient-sensor MOT test.

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.

Related guides

Car diagnostic test cost: compare the scopeUK booking marketplaces currently publish diagnostic averages of about £52–£65. Engine management light on: steady or flashing?A steady engine management light means the computer has stored a fault. Drive with caution and get the code read. A flashing light is different — stop when it is safe.
P0001Fuel Volume Regulator Control Circuit/Open P0002Fuel Volume Regulator Control Circuit Range/Performance P0003Fuel Volume Regulator Control Circuit Low P0004Fuel Volume Regulator Control Circuit High P0005Fuel Shutoff Valve 'A' Control Circuit/Open P0006Fuel Shutoff Valve 'A' Control Circuit Low P0007Fuel Shutoff Valve 'A' Control Circuit High P0008Engine Position System Performance

P0071 — quick answers

Is it safe to drive with P0071?

Do not drive. We have no verified driving guidance for P0071. Do not drive until checked. An implausible outside-air reading is still an engine-management fault when the lamp is on.

Will P0071 fail my MOT?

MOT requires the engine malfunction indicator lamp to be off. P0071 does not create a separate ambient-sensor MOT test.

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.