Oil Change Reset Button Circuit Short To Ground
The oil change reset button circuit has an electrical short directly to ground, preventing proper signal transmission to the ECU. Think of it like a light switch where the wire is touching the metal frame instead of properly completing the circuit.
The ECU monitors the oil change reset button circuit for a high voltage signal when the button is pressed. It expects a clean signal transition from high to low voltage; a short to ground keeps the signal at 0V continuously, preventing the ECU from detecting button presses.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Button Circuit Voltage | 5V at rest, drops to 0V when pressed | Stays at 0V continuously or reads below 0.5V at rest |
| Signal Resistance | High impedance at rest, low when activated | Continuous short reading, resistance near 0 ohms to ground |
Code B1379 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, B1379 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.