Wiper Rear High Limit Input Circuit Open
The rear wiper control circuit has an open connection, like a broken wire preventing power from reaching the wiper motor. The ECU can't detect the proper high-limit signal needed to operate the rear wiper.
The ECU monitors the rear wiper high-limit input circuit for a valid voltage signal when the wiper is commanded on. This signal confirms the motor has reached its parked position and the circuit is functioning. An open circuit prevents voltage from returning to the ECU, triggering the fault.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| High-Limit Input Voltage | 0.5-4.5V when activated | Below 0.2V or open circuit detected |
| Circuit Continuity | Complete path to ground | Open connection or broken wire |
Code B1827 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, B1827 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.