LF LAMP LOW BEAM CIRCUIT Failure
The left front headlight's low beam isn't working properly—the car's computer detected a circuit problem, like a broken wire in a lamp that won't light up. This could be a burned-out bulb, bad wiring, or a faulty headlight module.
The body control module monitors the low beam circuit's current draw and voltage supply to the left front lamp. When current flow drops below expected thresholds or voltage doesn't reach the bulb, it logs a fault. The ECU expects normal current draw during low beam operation.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Low Beam Current Draw | 50-60 amps typical | Below 10 amps or open circuit |
| Circuit Voltage | 12-14V at bulb | Below 9V or no voltage detected |
Code B2501 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.
Once the fault is repaired, B2501 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.