B1827: Rear Wiper High Limit Switch Open
Diagnostic trouble code B1827 indicates that the Body Control Module (BCM) or rear wiper control module has detected an open circuit in the high limit switch input of the rear wiper motor. This switch signals when the wiper blade reaches its maximum travel position. An open circuit prevents the module from accurately detecting the wiper position, disabling automatic operation and the park function.
1. Commonly Affected Makes
2. Most Common Causes
- Open circuit in the high limit switch signal wire between the rear wiper motor and the BCM/module
- Loose, corroded, or damaged terminals in the rear wiper motor connector
- Failed internal park/limit switch within the rear wiper motor assembly
- Faulty BCM or rear wiper control module
3. Symptoms You Will Notice
- Rear wiper does not park in the correct position
- Rear wiper operates erratically or stops mid-cycle
- Rear wiper fails to operate at all
- Automatic rear wiper function disabled
4. Step-by-Step Diagnosis
Inspect the rear wiper motor connector for corrosion, damage, or loose terminals
Check continuity of the high limit switch signal wire between the motor and BCM
Test the high limit switch inside the wiper motor for proper operation
If wiring and switch are good, suspect a faulty BCM or rear wiper module
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, it is generally safe to drive, but the rear wiper may not function correctly, which could reduce visibility in rain or snow.
How much does it cost to fix?▼
Repair costs typically range from $100 to $400, depending on whether the issue is a simple wiring repair or requires replacing the wiper motor or BCM.