P0112 fault code: Intake Air Temperature Sensor 1 Circuit Low

P0112 means “Intake Air Temperature Sensor 1 Circuit Low” — a fuel and air metering fault in the powertrain.

Can I DIY?

Professional-only boundary. Confirm P0112; a low IAT-1 circuit is not a published pin-test on this page.

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 P0112

Do not drive. Intake air temperature sensor 1 is reading too low on the circuit, which can make the computer treat warm air as if it were freezing and over-fuel.

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

  • Intake Air Temperature Sensor 1 Circuit Low: Registration number
  • Intake Air Temperature Sensor 1 Circuit Low: Exact code P0112 and whether it is current
  • Intake Air Temperature Sensor 1 Circuit Low: Outside temperature and whether the engine was heat-soaked
  • Intake Air Temperature Sensor 1 Circuit Low: Any work on the mass air-flow housing, where sensor 1 often lives
P01xxFuel and air metering
MOT fail riskif the warning light stays on

What does P0112 mean?

P0112 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P01xx block, which covers fuel and air metering. The stored description is “Intake Air Temperature Sensor 1 Circuit Low”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0112 fail an MOT?

An illuminated engine management light is a Major defect at MOT until the fault is repaired and the lamp stays off. P0112 is a low circuit on intake-air temperature sensor 1, not an MOT cold-start check.

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.
P0100Mass or Volume Air Flow Circuit P0101Mass or Volume Air Flow Circuit Range/Performance P0102Mass or Volume Air Flow Circuit Low Input P0103Mass or Volume Air Flow Circuit High Input P0104Mass or Volume Air Flow Circuit Intermittent P0105Manifold Absolute Pressure/Barometric Pressure Circuit P0106Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance P0107Manifold Absolute Pressure/Barometric Pressure Circuit Low Input

P0112 — quick answers

Is it safe to drive with P0112?

Do not drive. We have no verified driving guidance for P0112 — treat as do not drive until checked. A low IAT-1 circuit is electrical; it is not a cold-weather driving tip.

Will P0112 fail my MOT?

An illuminated engine management light is a Major defect at MOT until the fault is repaired and the lamp stays off. P0112 is a low circuit on intake-air temperature sensor 1, not an MOT cold-start check.

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.