AutoCodes – GMC – B3970 GMC

B3970 GMC Code - Output Driver Module Performance

Quick Answer

The Body Control Module (BCM) internally grounds the driver door unlock relay control circuit for the driver door unlock relay when it receives an unlock switch signal from either door lock switch. Common causes include Faulty Driver Door Unlock Relay, Driver Door Unlock Relay harness is open or shorted, Driver Door Unlock Relay 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: B3970 GMC indicates Output Driver Module Performance.
Common causes: Common causes include Faulty Driver Door Unlock Relay, Driver Door Unlock Relay harness is open or shorted, Driver Door Unlock Relay 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.

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Code Popularity 463

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 25, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3970 GMC Description

The Body Control Module (BCM) internally grounds the driver door unlock relay control circuit for the driver door unlock relay when it receives an unlock switch signal from either door lock switch. When the BCM grounds the driver door unlock relay control circuit the driver door unlock relay is energized and unlocks the driver door. The Diagnostic Trouble Code (DTC) will set if the driver door unlock relay control circuit is shorted to ground or open for more then one second.

OBDII Code B3970 GMC - Output Driver Module Performance - AutoCodes.com — B3970 GMC Code - Output Driver Module Performance

What does this mean?

What are the Possible Causes of the DTC B3970 GMC?

Faulty Driver Door Unlock Relay
Driver Door Unlock Relay harness is open or shorted
Driver Door Unlock Relay circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3970 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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3970 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.

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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 B3970 GMC Code

1. What are the common symptoms of OBDII code B3970 GMC (Output Driver Module Performance)?

- Common symptoms may include issues with the vehicle's lighting system, such as malfunctioning brake lights, turn signals, or interior lights.

2. What are some possible causes of OBDII code B3970 GMC?

- Possible causes of this code may include a faulty output driver module, wiring issues, a blown fuse, or a problem with the body control module.

3. How can I diagnose OBDII code B3970 GMC?

- Diagnosing this code typically involves using a diagnostic scanner to retrieve the code, followed by inspecting the output driver module, checking the wiring, and testing the related components.

4. Can OBDII code B3970 GMC be repaired at home?

- Depending on the root cause, some DIY enthusiasts may be able to repair this code at home by replacing the faulty output driver module, fixing wiring issues, or resetting the body control module.

5. Is it safe to continue driving with OBDII code B3970 GMC illuminated?

- It is not recommended to continue driving with this code illuminated, as it may lead to safety hazards such as non-functioning brake lights or turn signals.

6. How much does it typically cost to repair OBDII code B3970 GMC at a mechanic or dealership?

- The cost of repairing this code can vary depending on the specific cause and the labor rates of the service provider. It's advisable to get a quote from a mechanic or dealership.

7. Can a low battery voltage trigger OBDII code B3970 GMC?

- Yes, a low battery voltage can potentially trigger this code as it may affect the proper functioning of the output driver module or other related components.

8. Are there any preventive maintenance tips to avoid OBDII code B3970 GMC?

- Regularly checking and maintaining the vehicle's electrical system, including the output driver module and wiring, can help prevent issues that may trigger this code.

9. Will disconnecting the battery reset OBDII code B3970 GMC?

- Disconnecting the battery may reset the code temporarily, but if the underlying issue is not addressed, the code is likely to reappear once the problem resurfaces.

10. How urgent is it to address OBDII code B3970 GMC once it's detected?

- It is advisable to address this code promptly to ensure the proper functioning of essential vehicle lighting systems and prevent potential safety risks on the road.