Ambient Air Temperature Sensor Circuit B High

Common symptoms

What you'll notice

• Check the sensor's wiring for any damage or loose connections.
• Test the sensor using a multimeter to check for proper resistance readings.
• Replace the ambient air temperature sensor if it is found to be faulty.
• Inspect the engine's air intake system for any blockages or restrictions.
• Reset the vehicle's computer by disconnecting the battery for a few minutes and then reconnecting it to see if the error code clears.

Common causes

Most likely first

1. Faulty ambient air temperature sensor
2. Wiring or connector issues with the ambient air temperature sensor
3. Faulty engine coolant temperature sensor
4. Issues with the engine control module (ECM) or powertrain control module (PCM)
5. Faulty climate control system

How to diagnose & fix

Work through it in order

1. Engine may experience difficulty starting in colder temperatures
2. Engine may not start at all in extreme cold conditions
3. Erratic engine idle or fluctuating idle speed
4. Poor fuel efficiency or decreased fuel mileage
5. Illumination of the "Check Engine" or "Service Engine Soon" light