Signal wire shorted to earth or chafed against bodywork or another component; Faulty intake air temperature sensor 2 with an internal short; Damaged, corroded or water-contaminated connector or terminals at the sensor; Signal wire shorted to another circuit, or a wiring harness fault; Poor sensor reference or earth connection shared with other sensors; Fault in the engine control unit's sensor input circuit.

P0097

Intake Air Temperature Sensor 2 Circuit Low Bank 1.

Generic
Powertrain
Generic code
Low severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
0: AreaFuel and air metering, auxiliary emission controls
97: FaultThe specific fault in that area

What it means

P0097 means the engine control unit has seen a voltage from intake air temperature sensor 2 on bank 1 that is lower than expected, which it reads as an implausibly high air temperature. The sensor's location and what it is used for vary by model and engine, so it is often fitted on turbocharged or supercharged engines after the compressor or charge cooler. The code is set when the signal stays below the expected range for long enough to be judged a fault.

Symptoms

Engine warning light on
Hesitation or reduced power, as the control unit may limit boost or timing
Poor fuel economy
Rough running or difficult starting in some cases
Possible hard starting or poor running when cold

Possible causes

Signal wire shorted to earth or chafed against bodywork or another componentlikely
Faulty intake air temperature sensor 2 with an internal shortlikely
Damaged, corroded or water-contaminated connector or terminals at the sensorpossible
Signal wire shorted to another circuit, or a wiring harness faultpossible
Poor sensor reference or earth connection shared with other sensorspossible
Fault in the engine control unit's sensor input circuitrare

How to diagnose

Read all stored and pending codes and the freeze frame data, noting engine temperature, load and whether other temperature or sensor circuit codes are present.
Check the live data for intake air temperature 2 and compare it with intake air temperature 1 and coolant temperature on a cold engine; they should be similar. An implausibly high reading suggests a low-voltage fault.
Inspect the sensor, connector and wiring for chafing, heat damage, moisture, corrosion and bent or pushed-back terminals.
With the connector unplugged and the ignition on, check the sensor signal voltage at the harness matches the reference value for that model; if it stays low, there is a short to earth in the harness.
Wiggle-test the harness with the engine running and watch the live data for sudden jumps.
Measure the sensor resistance and compare it with the manufacturer's temperature-resistance table for that model.
Check the wiring continuity and for shorts to earth between the sensor and the control unit, following the wiring diagram for that vehicle.
Clear the code and road test to confirm that it does not return.

How to fix

Repair or replace the damaged wiring section, and secure and protect the harness where it was chafing.
Replace intake air temperature sensor 2 if its resistance or signal is out of specification.
Clean, repair or replace the connector and terminals, and fix any water ingress.
Restore a good reference or earth connection if it is found to be faulty.
Repair the control unit input only after wiring and sensor faults have been ruled out, following the manufacturer's procedure.

Can I keep driving?

Low severity

The car can usually be driven for a short time, but book it in soon as the control unit may be using a default air temperature and limiting performance. If it is running badly or losing power noticeably, have it checked sooner.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.