AutoCodes – GMC – B3578 GMC

B3578 GMC Code - Output Air Temperature Sensor 6 Circuit

Quick Answer

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. Common causes include Faulty Output Air Temperature Sensor 6, Output Air Temperature Sensor 6 harness is open or shorted, Output Air Temperature Sensor 6 circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: B3578 GMC indicates Output Air Temperature Sensor 6 Circuit.
Common causes: Common causes include Faulty Output Air Temperature Sensor 6, Output Air Temperature Sensor 6 harness is open or shorted, Output Air Temperature Sensor 6 circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 1,539

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 09, 2020

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B3578 GMC Description

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.

OBDII Code B3578 GMC - Output Air Temperature Sensor 6 Circuit - AutoCodes.com — B3578 GMC Code - Output Air Temperature Sensor 6 Circuit

What does this mean?

What are the Possible Causes of the DTC B3578 GMC?

Faulty Output Air Temperature Sensor 6
Output Air Temperature Sensor 6 harness is open or shorted
Output Air Temperature Sensor 6 circuit poor electrical connection
Faulty Heating, Ventilation, and Air Conditioning (HVAC) Control Module

How to Fix the DTC B3578 GMC?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code Tech Notes

B3578 05: Output Air Temperature Sensor 6 Circuit Short to Battery or Open
B3578 02: Output Air Temperature Sensor 6 Circuit Short to Ground

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3578 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the B3578 GMC code?

Need more information on how to fix the B3578 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3578 GMC code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B3578 GMC Code

1. What are the common symptoms of OBDII code B3578 in a GMC related to the Output Air Temperature Sensor 6 Circuit?

- Common symptoms include poor engine performance, reduced fuel efficiency, and potential issues with the vehicle's heating and cooling systems.

2. What are some possible causes of OBDII code B3578 in a GMC?

- Possible causes may include a faulty output air temperature sensor, damaged wiring or connectors in the sensor circuit, or issues with the engine control module.

3. How can I diagnose the source of OBDII code B3578 in my GMC?

- To diagnose the issue, you can use an OBDII scanner to retrieve the specific fault code and then inspect the output air temperature sensor, wiring, and connectors for any visible damage or wear.

4. What are some repair tips for fixing OBDII code B3578 in a GMC?

- Repair tips may include replacing the faulty output air temperature sensor, repairing or replacing damaged wiring or connectors, and clearing the fault code with an OBDII scanner.

5. Can I drive my GMC with OBDII code B3578 present?

- It is not recommended to drive your vehicle with this fault code present, as it can lead to further damage and potential safety hazards. It's best to address the issue promptly.

6. How critical is it to repair OBDII code B3578 in a GMC?

- While the severity of the issue may vary, it is important to address this fault code promptly to prevent potential damage to other components and ensure optimal engine performance.

7. Is it possible to reset OBDII code B3578 in a GMC without making any repairs?

- Resetting the fault code without addressing the underlying issue is not recommended, as the problem will likely persist and may lead to further complications down the road.

8. How much does it typically cost to repair OBDII code B3578 in a GMC?

- The cost of repairs can vary depending on the specific cause of the fault code, but it may involve expenses for parts and labor, with costs ranging from a few hundred to over a thousand dollars.

9. Can a DIY enthusiast fix OBDII code B3578 in a GMC, or is professional help recommended?

- While some individuals with automotive repair experience may be able to address this issue themselves, it is generally recommended to seek professional help to ensure the problem is diagnosed and repaired correctly.

10. Are there any preventive measures to avoid OBDII code B3578 in a GMC in the future?

- Regularly inspecting and maintaining the vehicle's sensors, wiring, and connectors, as well as following the manufacturer's recommended maintenance schedule, can help prevent issues like OBDII code B3578 from occurring.