Rear Wiper MUX Circuit Error

SYMPTOM
REAR WIPER MUX CIRCUIT ERROR

WHEN MONITORED
The BCM interfaces with HVAC control module to perform the rear wiper function. The HVAC Control Head sends the BCM a voltage level which is based on the function selected. This level is below 5.0 volts.

SET CONDITION
If the BCM does not detect a valid voltage within 10 seconds after ignition ON.

POSSIBLE CAUSES
- Wiper switch signal circuit shorted to B(+)
- Rear wiper MUX circuit trouble code
- Open ground circuit/HVAC Control Module
- Defective BCM - rear wiper switch default