Driver Rear Door Ajar Circuit Open
The driver's rear door isn't closing properly or the sensor detecting it is broken, like a light switch that won't turn off. Your vehicle's computer detected an open circuit in the door ajar warning system.
The ECU monitors the driver rear door latch switch for a closed-circuit signal (ground). When the door closes, the switch should complete the circuit; when open, it breaks it. An open circuit fault means the ECU detects no ground signal when expecting one.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Door latch switch voltage | 0V (closed/grounded) or 12V (open) | Continuous high voltage or no signal detected |
| Circuit continuity | Complete circuit path to ECU | Open circuit/broken wire detected |
Code B2243 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, B2243 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.