Engine-Codes - Chevrolet - B0178 Chevrolet

B0178 Chevrolet Code - Output Air Temperature Sensor 2 Circuit

- Code Popularity: 3,787 Views
- Repair Importance Level: 1/3
- Repair Difficulty Level: 2/3
Table of contents

|What are the Possible Causes of the Code B0178 Chevrolet?

  • Faulty Output Air Temperature Sensor 2
  • Output Air Temperature Sensor 2 harness is open or shorted
  • Output Air Temperature Sensor 2 circuit poor electrical connection
  • Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module

|How to Fix the B0178 Chevrolet Code?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

|Code B0178 Chevrolet Tech Notes

B0178 05: Output Air Temperature Sensor 2 Circuit Short to Battery or Open
B0178 02: Output Air Temperature Sensor 2 Circuit Short to Ground

|What is the Cost to Diagnose the Code B0178 Chevrolet?

Labor: 1.0

The cost to diagnose the B0178 Chevrolet code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

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|What are Code B0178 Chevrolet Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

|What Does the B0178 Chevrolet Code Mean?

Air temperature sensors allow the Heating, Ventilation, and Air Conditioning (HVAC) Control Module to monitor the temperature of the discharge air in the HVAC ducts. The module applies 5 volts to internal input resistors that are connected to the signal circuits of the air temperature sensors. The module provides ground to the air temperature sensors through the low reference circuit. The HVAC control module monitors the voltage drops across the air temperature sensors and uses the inputs for automatic control calculations. When the duct air temperatures are cold, the resistances of the sensors are high and the voltage signals are high. When the duct air temperatures are hot, the resistances of the sensors are low and the voltage signals are low. The HVAC control module converts the voltage values to count values where 1 volt is approximately equal to 51 counts.

B0178 Chevrolet Code - Output Air Temperature Sensor 2 Circuit

|Need more Information on the B0178 Chevrolet Code?

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|Need Help with the B0178 Chevrolet Code?

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