B0178
Output Air Temperature Sensor 2 Circuit
B0178 is an OBD-II diagnostic trouble code meaning: Output Air Temperature Sensor 2 Circuit. Common causes: open/short circuit in wiring harness, poor contact in the sensor connector. Estimated repair cost: $22–111.
Symptoms
- Incorrect air temperature in the second zone of the cabin
- The climate control for the passenger does not work / does not work correctly
- Hot/cold air on one side only
- HVAC Error Indication
Causes
- Open/short circuit in wiring harness
- Poor contact in the sensor connector
- Air temperature sensor malfunction
- HVAC Control Module Problems
- Contact corrosion
How to Fix
- Visual inspection of the wiring harness and connectors
- Checking sensor resistance (compare with specs)
- Checking voltage and ground in the sensor circuit
- Replace the sensor if necessary
- Repair/replacement of damaged wires
- Cleaning oxidized contacts
- Resetting the error and checking the system operation
Related codes
Error B0178 by Vehicle Brand
FAQ
What does the B0178 code mean?
B0178 is an OBD-II diagnostic trouble code that indicates: Output Air Temperature Sensor 2 Circuit
What causes a B0178 error code?
The most common causes of B0178 include: Open/short circuit in wiring harness; Poor contact in the sensor connector; Air temperature sensor malfunction; HVAC Control Module Problems.
How do I fix a B0178 diagnostic trouble code?
To fix B0178: Visual inspection of the wiring harness and connectors. Checking sensor resistance (compare with specs). Checking voltage and ground in the sensor circuit. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with B0178?
Yes, but get it checked soon
How much does it cost to fix B0178?
The estimated repair cost for B0178 is $22–111. Actual cost depends on your vehicle, location, and labor rates.
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