AutoCodes – GMC – B1400 GMC

B1400 GMC Code - Control Module Supply Circuit 2

Quick Answer

The vehicle control modules or sensors monitor the system voltage to verify the system voltage is within the normal operating range. Common causes include Low battery voltage, Faulty Control Module, Control Module harness is open or shorted. 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: B1400 GMC indicates Control Module Supply Circuit 2.
Common causes: Common causes include Low battery voltage, Faulty Control Module, Control Module harness is open or shorted.
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 859

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 Jul 11, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B1400 GMC Description

The vehicle control modules or sensors monitor the system voltage to verify the system voltage is within the normal operating range. Damage to components, and incorrect data can occur when the voltage is out of range. The vehicle has multiple Control Modules that will set this Diagnostic Trouble Code (DTC).

OBDII Code B1400 GMC - Control Module Supply Circuit 2 - AutoCodes.com — B1400 GMC Code - Control Module Supply Circuit 2

What does this mean?

What are the Possible Causes of the DTC B1400 GMC?

Low battery voltage
Faulty Control Module
Control Module harness is open or shorted
Control Module circuit poor electrical connection

How to Fix the DTC B1400 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 B1400 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 B1400 GMC code?

Need more information on how to fix the B1400 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1400 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

B1400 2014 GMC Sierra — Control Module Supply Circuit 2
B1400 2015 GMC Sierra — Control Module Supply Circuit 2
B1400 2016 GMC Sierra — Control Module Supply Circuit 2
B1400 2017 GMC Sierra — Control Module Supply Circuit 2
B1400 2018 GMC Sierra — Control Module Supply Circuit 2

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 B1400 GMC Code

1. What are the common symptoms of OBDII code B1400 GMC (Control Module Supply Circuit 2)?

- Common symptoms include engine stalling, rough idling, poor acceleration, and possible illumination of the Check Engine light.

2. What can cause the OBDII code B1400 GMC to appear?

- The code may be triggered by a faulty control module supply circuit, damaged wiring, a blown fuse, or a malfunctioning control module itself.

3. How can I diagnose the cause of OBDII code B1400 GMC?

- Diagnosing the issue typically involves inspecting the control module supply circuit, checking for wiring damage, testing the control module voltage, and scanning for other related trouble codes.

4. Can I still drive my vehicle with the OBDII code B1400 GMC present?

- It is not recommended to drive your vehicle with this code present, as it can lead to performance issues and potential further damage if left unresolved.

5. What are some repair tips for fixing OBDII code B1400 GMC?

- Repair tips include checking and repairing any damaged wiring, replacing blown fuses, testing and possibly replacing the control module, and clearing the trouble codes after the repair.

6. How much does it typically cost to repair OBDII code B1400 GMC?

- The cost of repair can vary depending on the underlying cause, but it may range from a couple of hundred dollars for simple fixes like fuse replacement to over a thousand dollars for control module replacement.

7. Can a DIY enthusiast fix OBDII code B1400 GMC at home?

- DIY enthusiasts with automotive repair experience and the necessary tools can attempt to fix this code at home, especially for tasks like checking wiring and replacing fuses. However, more complex issues may require professional help.

8. Is it important to address OBDII code B1400 GMC immediately?

- Yes, it is important to address the code promptly to prevent potential engine performance issues, further damage to components, and to ensure the vehicle operates safely.

9. Will resetting the OBDII system clear the B1400 GMC code?

- Resetting the OBDII system may temporarily clear the code, but if the underlying issue causing the code is not fixed, it is likely to reappear after some driving cycles.

10. How long does it take to repair OBDII code B1400 GMC?

- The repair time can vary based on the specific cause of the code and the complexity of the repair needed. Simple fixes may take a few hours, while more involved repairs could require a day or more.