Oil Change Lamp Circuit Open
Your vehicle's oil change reminder circuit has an electrical break, like a cut wire in a light switch. The ECU can't communicate with the oil life monitoring system to display service reminders.
The ECU monitors the continuity and voltage across the oil change lamp circuit, expecting a complete electrical path with proper voltage levels. When the circuit opens or resistance becomes too high, the ECU detects a loss of signal and triggers the fault code. The system performs periodic continuity checks to ensure the lamp driver circuit and associated wiring are intact.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Circuit Continuity | Complete path, <5 ohms resistance | Open circuit, >10 ohms or infinite resistance |
| Lamp Driver Voltage | 12V supply available at connector | <8V or no voltage detected |
Code B1375 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, B1375 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.