Wiper Rear Mode Select Switch Circuit Short To Battery
The rear wiper mode switch circuit is stuck at battery voltage instead of varying properly, like a light switch jammed in the on position. The ECU detects this abnormal high voltage signal and can't control the rear wiper modes correctly.
The ECU monitors the rear wiper mode select switch voltage, which should vary between ground and battery voltage depending on switch position. When the circuit shorts to battery voltage, the signal remains high and doesn't vary as the driver changes modes, preventing proper wiper speed control.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Mode Switch Voltage | 0.5V to 4.5V (varying by position) | Continuously above 4.5V (shorted to battery) |
| Signal Variance | Changes with switch position | No voltage change detected |
Code B1613 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, B1613 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.