AutoCodes – GMC – B3109 2018 GMC Sierra

B3109 2018 GMC Sierra Code - Keyless Entry Transmitter 1 Battery

Quick Answer

With each press of a keyless entry transmitter button, a message containing the current battery state of the transmitter is sent to the Remote Control Door Lock Receiver (RCDLR), along with the commanded keyless entry function. Common causes include Low Keyless Entry Transmitter Battery, Faulty Keyless Entry Transmitter. 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: B3109 2018 GMC Sierra indicates Keyless Entry Transmitter 1 Battery.
Common causes: Common causes include Low Keyless Entry Transmitter Battery, Faulty Keyless Entry Transmitter.
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 369

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 Jun 11, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3109 2018 GMC Sierra Description

With each press of a keyless entry transmitter button, a message containing the current battery state of the transmitter is sent to the Remote Control Door Lock Receiver (RCDLR), along with the commanded keyless entry function. The Remote Control Door Lock Receiver sends this to the Body Control Module (BCM) to perform the requested function. The Diagnostic Trouble Code (DTC) sets when three consecutive low-battery signals are received from the same transmitter.

OBDII Code B3109 2018 GMC Sierra - Keyless Entry Transmitter 1 Battery - AutoCodes.com — B3109 2018 GMC Sierra Code - Keyless Entry Transmitter 1 Battery

What does this mean?

What are the Possible Causes of the DTC B3109 2018 GMC Sierra?

Low Keyless Entry Transmitter Battery
Faulty Keyless Entry Transmitter

How to Fix the DTC B3109 2018 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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3109 2018 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 B3109 2018 GMC Sierra code?

Need more information on how to fix the B3109 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the 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 B3109 2018 GMC Sierra Code

1. What does OBDII code B3109 on a 2018 GMC Sierra indicate?

The B3109 code specifically refers to a problem with the Keyless Entry Transmitter 1 Battery.

2. What are the common symptoms of OBDII code B3109 in a 2018 GMC Sierra?

Common symptoms include issues with the keyless entry system, such as the remote not working properly or sporadically.

3. What are the possible causes of OBDII code B3109 on a 2018 GMC Sierra?

The most common cause is a weak or failing battery in the keyless entry transmitter.

4. How can I diagnose the issue related to OBDII code B3109 on my 2018 GMC Sierra?

You can start by replacing the battery in the Keyless Entry Transmitter 1 to see if that resolves the problem. If the issue persists, further inspection may be needed.

5. Can I repair OBDII code B3109 in my 2018 GMC Sierra myself?

Yes, replacing the battery in the Keyless Entry Transmitter 1 is a relatively simple DIY repair that may solve the problem.

6. Are there any troubleshooting tips for resolving OBDII code B3109 on a 2018 GMC Sierra?

Ensure that the replacement battery is the correct type and properly installed in the keyless entry transmitter to avoid further issues.

7. Will OBDII code B3109 on a 2018 GMC Sierra affect the vehicle's performance?

The B3109 code related to the keyless entry transmitter battery should not impact the overall performance of the vehicle but may cause inconvenience with the remote entry system.

8. How often should I replace the battery in the keyless entry transmitter of my 2018 GMC Sierra?

It is recommended to replace the battery in the keyless entry transmitter as soon as you notice any issues with its functionality.

9. Are there any long-term consequences of ignoring OBDII code B3109 on a 2018 GMC Sierra?

Continuing to ignore the B3109 code may result in complete failure of the keyless entry system, requiring more extensive repairs or replacements in the future.

10. Can I still drive my 2018 GMC Sierra with OBDII code B3109 present?

Yes, you can still drive the vehicle safely with the B3109 code related to the keyless entry transmitter battery, but it's recommended to address the issue promptly to avoid inconvenience.