KlaroFault codeP0074
MODERATEAmbient Air Temperature Sensor Circuit Intermittent
What this code means
Ambient Air Temperature Sensor Circuit Intermittent.
P0074 is a generic code: it means the same thing on every make. P0074 belongs to family P00xx — Fuel and air metering, auxiliary emission controls. Its page explains how to read a code and groups all its codes by part.
Type of fault
The signal drops out or jumps from time to time. This is typical of a poor contact: a loose or corroded connector, or a chafed wire that touches intermittently, often triggered by vibration or heat. The fault may disappear and come back; checking the wiring with the engine running is often revealing.
Ambient air temperature sensor
The ambient temperature sensor, usually behind the front bumper or in a door mirror, measures the outside temperature. The engine control unit uses it for some corrections, and it also feeds the dashboard display and the air conditioning.
What you notice
Wrong outside temperature on the dashboard, air conditioning that behaves oddly; the engine itself runs normally in most cases.
How to check it
Its location makes it vulnerable to knocks, gravel and water: check the sensor and its connector behind the bumper. Car parked for several hours, its reading in Klaro should be close to the intake air temperature.
Watch it live in Klaro
With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:
- Ambient air temperature
- Intake air temperature
What to do
Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.
Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →
How to read this code
- PPowertrain
- 0standardised code
- 0Fuel and air metering, auxiliary emission controls
- 74P0074
