AutoCodes – GMC – B3125 2016 GMC Sierra

B3125 2016 GMC Sierra Code - Driver Door Only Unlock Circuit

Quick Answer

The Body Control Module (BCM) supplies a 12-volt signal to the lock and unlock signal circuits of the driver and passenger door lock switches. Common causes include Faulty Driver Door Latch Assembly, Driver Door Latch Assembly harness is open or shorted, Driver Door Latch Assembly 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: B3125 2016 GMC Sierra indicates Driver Door Only Unlock Circuit.
Common causes: Common causes include Faulty Driver Door Latch Assembly, Driver Door Latch Assembly harness is open or shorted, Driver Door Latch Assembly 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 337

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Jun 11, 2023

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code B3125 2016 GMC Sierra Description

The Body Control Module (BCM) supplies a 12-volt signal to the lock and unlock signal circuits of the driver and passenger door lock switches. When the appropriate switch is pressed, a contact within the door lock switch closes providing a ground path for the signal circuit. The BCM will detect the voltage drop in the signal and will command the doors to perform the lock or unlock functions. The BCM may also receive a LOCK or UNLOCK command from the Keyless Entry Control Module.
The BCM, upon receipt of a lock switch lock or unlock signal, will supply voltage to the door lock actuator lock or unlock control circuits. Since the opposite side of the lock actuator is connected to the ground through the other lock actuator control circuit, the doors will then lock or unlock as commanded. The Diagnostic Trouble Code (DTC) sets when the BCM detects a short to ground or open/high resistance on a door latch control circuit.

OBDII Code B3125 2016 GMC Sierra - Driver Door Only Unlock Circuit - AutoCodes.com — B3125 2016 GMC Sierra Code - Driver Door Only Unlock Circuit

What does this mean?

What are the Possible Causes of the DTC B3125 2016 GMC Sierra?

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

How to Fix the DTC B3125 2016 GMC Sierra?

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

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3125 2016 GMC Sierra 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 B3125 2016 GMC Sierra code?

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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 B3125 2016 GMC Sierra Code

1. What does the OBDII code B3125 mean for a 2016 GMC Sierra?

Code B3125 indicates an issue with the Driver Door Only Unlock Circuit, which controls the driver's door unlock function.

2. What are common symptoms of code B3125 in a 2016 GMC Sierra?

Symptoms may include the driverâ€™s door failing to unlock, intermittent unlocking issues, or the driver's door unlocking only manually.

3. What causes the B3125 code in a 2016 GMC Sierra?

Common causes include a faulty door lock actuator, wiring issues, a malfunctioning door control module, or a software glitch.

4. Can a blown fuse cause the B3125 code?

Yes, a blown fuse associated with the door lock circuit can trigger this code.

5. How is the B3125 code diagnosed?

Diagnosis typically involves scanning for codes, inspecting wiring and connectors, testing the door lock actuator, and evaluating the door control module.

6. Can I still drive my 2016 GMC Sierra with the B3125 code?

Yes, this code typically does not affect drivability but may compromise convenience and security due to door locking issues.

7. How do I fix the B3125 code on my 2016 GMC Sierra?

Repairs may include replacing the door lock actuator, repairing damaged wiring, clearing software errors, or replacing the door control module.

8. Is the B3125 code expensive to repair?

The cost depends on the exact cause, but replacing a door lock actuator or repairing wiring is generally not very expensive.

9. Can a software update resolve the B3125 code?

In some cases, a software update to the body control module may resolve the issue, especially if itâ€™s caused by a programming glitch.

10. Do I need a professional to fix the B3125 code?

While some repairs like checking fuses and connectors can be done by DIYers, diagnosing and repairing wiring or module issues may require professional assistance.