Case IH 2636-03 - BCM – BCM: Front wiper high speed motor - short circuit to B+

The front wiper high-speed motor circuit is experiencing a short circuit to B+ (a higher-than-normal voltage source, typically positive 12 volts). The most likely cause is a damaged wiring harness (chafed wires touching a power source) or an internal short within the wiper motor itself.

• MAGNUM AFS Connect

1. 1

   Disconnect the front wiper motor and check the resistance at the cable end to isolate the harness from the motor.

2. 2

   Inspect the wiring harness for damage. Measure for opens and shorts to a voltage source using a multimeter.

3. 3

   Check the resistance directly at the wiper motor pins to determine if the internal motor windings are shorted.

4. 4

   Check the ECU/BCM supply voltage to ensure the controller is not outputting excessive voltage.

1. 1

   Trace wiring harness

   Trace the front wiper motor wiring harness back to the BCM.

2. 2

   Repair or replace wiring harness

   Repair or replace the damaged section of the wiring harness if a short to power is found.

3. 3

   Replace wiper motor

   Replace the front wiper motor if the internal circuitry is shorted.

4. 4

   Clear codes and retest

   Clear the fault codes from the BCM and retest the wiper system on high speed to verify the repair.