AutoCodes – GMC – B1390 GMC

B1390 GMC Code - Control Module Supply Circuit 1

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: B1390 GMC indicates Control Module Supply Circuit 1.
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 4,343

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 B1390 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 B1390 GMC - Control Module Supply Circuit 1 - AutoCodes.com — B1390 GMC Code - Control Module Supply Circuit 1

What does this mean?

What are the Possible Causes of the DTC B1390 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 B1390 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 B1390 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 B1390 GMC code?

Need more information on how to fix the B1390 GMC code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B1390 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

B1390 2014 GMC Sierra — Control Module Supply Circuit 1
B1390 2015 GMC Sierra — Control Module Supply Circuit 1
B1390 2016 GMC Sierra — Control Module Supply Circuit 1
B1390 2017 GMC Sierra — Control Module Supply Circuit 1
B1390 2018 GMC Sierra — Control Module Supply Circuit 1

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 B1390 GMC Code

1. What are the common symptoms of OBDII code B1390 GMC?

The common symptoms of OBDII code B1390 GMC include issues with starting the vehicle, poor engine performance, and potential stalling.

2. What are the possible causes of OBDII code B1390 GMC?

Possible causes of OBDII code B1390 GMC include a faulty control module, damaged wiring or connectors in the supply circuit, or a weak or dead battery.

3. How can I diagnose OBDII code B1390 GMC?

Diagnosing OBDII code B1390 GMC involves using a scan tool to read the code, checking the voltage supply to the control module, inspecting wiring and connectors for damage, and testing the battery's condition.

4. Can a weak battery cause OBDII code B1390 GMC?

Yes, a weak or dead battery can cause OBDII code B1390 GMC as it may not provide sufficient power to the control module.

5. How can I repair OBDII code B1390 GMC?

To repair OBDII code B1390 GMC, you may need to replace the faulty control module, repair or replace damaged wiring or connectors, and ensure the battery is in good condition.

6. Is it safe to continue driving with OBDII code B1390 GMC?

It is not recommended to continue driving with OBDII code B1390 GMC as it can lead to further damage to the vehicle and potential safety hazards.

7. Can OBDII code B1390 GMC be intermittent?

Yes, OBDII code B1390 GMC can be intermittent, especially if the issue is related to loose connections or sporadic electrical faults.

8. How much does it cost to repair OBDII code B1390 GMC?

The cost to repair OBDII code B1390 GMC can vary depending on the specific cause of the issue, but it may involve parts and labor expenses.

9. Can I reset OBDII code B1390 GMC with a simple battery disconnect?

While disconnecting the battery may clear the code temporarily, it is not a reliable long-term solution to address the underlying issue causing OBDII code B1390 GMC.

10. Do I need a professional mechanic to fix OBDII code B1390 GMC?

It is recommended to consult a professional mechanic to properly diagnose and repair OBDII code B1390 GMC to ensure the issue is resolved correctly and efficiently.