What does it mean?
B2185 is a Body (airbags, seat belts, body electronics) fault code. It indicates: Ignition Unlock Run/Start Control Circuit High .
Symptoms
- Rear wiper runs continuously and will not switch off
- Rear wiper does not park and stops mid sweep on the glass
- Rear wiper completely dead because the module has disabled the output
- Rear washer operating at the wrong time or not at all
- Rear wiper fuse blowing
- Rear wiper dry sweeping and smearing the glass
Likely causes
- Rear wiper switch or rotary control with contacts stuck closed
- Wiring broken or chafed inside the flexible boot between the body and the tailgate, the classic failure point for rear wiper circuits
- Water in the tailgate corroding the connector or the switch
- Signal wire shorted to ground behind the dash or along the headliner run to the tailgate
- Rear wiper motor circuit damaged and feeding a ground into the select line
- Corroded terminals at the body module connector
- Aftermarket wiring for a reversing camera or spoiler light spliced into the same loom
- Body module input failure, once the switch and wiring are cleared
How to fix it
- Confirm the manufacturer definition and the select switch D pin for this vehicle
- Watch the rear wiper request in live data with the switch at rest
- Disconnect the rear wiper switch and see whether the request clears
- Measure the input circuit resistance to ground with the switch unplugged, it must read open
- Pull back the rubber boot at the tailgate hinge and flex the loom while watching live data, look for broken strands under intact insulation
- Inspect the tailgate connectors for water and green corrosion
- Repair or replace the damaged section of wiring with correctly sized flexible cable
- Clear the code, test every rear wiper mode and confirm the blade parks correctly