Keyless Entry Transmitter 1 — Low Battery (three consecutive low-battery signals) (GM)
The B3109 code means the vehicle's onboard diagnostic system has detected: Keyless Entry Transmitter 1 — Low Battery (three consecutive low-battery signals) (GM). This is a low severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- hard
- Estimated cost
- Varies — depends on the specific component this manufacturer-specific code points to on your vehicle. Diagnose before buying parts.
Manufacturer-specific code. B3109 is a manufacturer-specific DTC, so its exact definition can differ by make, model, and year. Use the meaning above as a general guide, and always confirm it against your vehicle manufacturer's official service information (or a make-specific scan tool) before diagnosing or replacing parts.
What Are the Symptoms of B3109?
- Check Engine or a related warning light on
- Exact symptoms depend on the specific system this code covers for your make
- A make-specific scan reveals which subsystem and circuit is involved
What Causes B3109? (Most Likely First)
- A fault in the specific component or circuit this code monitors (the exact part varies by manufacturer) High
- Damaged wiring, a corroded connector, or a poor ground in that circuit Moderate
- A related sensor or control module reporting or causing the fault Moderate
Can I Still Drive with B3109?
Yes, but fix soon. B3109 is rated low severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring the light.
Frequently Asked Questions
Does B3109 mean the same thing on every vehicle?
No. B3109 is a manufacturer-specific diagnostic trouble code, so its exact meaning varies by make, model, and year. Always confirm it against your vehicle manufacturer's service information before diagnosing or replacing parts.
What does B3109 most likely indicate?
Keyless Entry Transmitter 1 — Low Battery (three consecutive low-battery signals) (GM). Treat this as a general guide and verify the specifics for your vehicle.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose B3109?
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Confirm your exact make, model, and year first — B3109 is manufacturer-specific and can mean different things across brands.
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Read B3109 with an enhanced/make-specific scan tool and check your manufacturer's official service information for the precise definition and procedure.
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Inspect the wiring, connectors, and grounds for the indicated circuit before replacing any part.
Which Vehicles Commonly Get B3109?
- 2012-2022 Lincoln Navigator
- 2014-2023 Lincoln Aviator
- 2016-2023 Ford F-250
- 2010-2020 Lincoln MKZ
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