Mirror Switch Assembly Circuit Open
The mirror control switch has a broken electrical connection, like a light switch with a severed wire that can't send signals. The vehicle's computer detected an open circuit where the switch should be continuously providing a signal path.
The ECU monitors voltage and continuity on the mirror switch circuit, expecting a complete path to ground when buttons are pressed and a high-impedance state at rest. When the circuit opens, the ECU detects an abnormal voltage condition that doesn't match the expected signal pattern for any valid switch position.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Switch Circuit Continuity | Continuity present with valid voltage transitions | Open circuit / no continuity detected |
| Signal Voltage | 0-12V transitions based on switch input | Stuck high or no response to button press |
Code B2337 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, B2337 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.