Case IH 520570-06 - BCM – BCM: Rear Wiper Motor Short Circuit to Ground

A "short circuit to ground" indicates that the electrical wiring supplying power to the rear wiper motor, or the motor itself, has an unintended connection to the vehicle's ground (chassis or ground wire). This condition typically occurs at the high-side power stage or inside a relay, causing excessive current draw that the system detects as a fault.

• MAGNUM AFS Connect
• Case IH Farmall Series (Farmall 115C)
• Case IH MXM Series (MXM130, MXM140, MXM190)
• Case Wheel Loaders (621E Tier 3)

1. 1

   Inspect the wiring harness leading to the rear wiper motor for broken, disconnected, or chafed wires that may be touching the bare metal of the cab.

2. 2

   Test the rear wiper relay. The short circuit to ground can often occur internally inside the relay.

3. 3

   Check the high-side power stage for shorts to ground or external sources.

1. 1

   Disconnect Power

   Disconnect the battery before servicing electrical components to prevent memory loss or further electrical damage.

2. 2

   Access the Motor

   Remove the rear wiper motor plastic cover to access the motor and harness connections.

3. 3

   Repair Wiring/Relay

   If the diagnostic checks revealed a short in the wiring harness or a defective relay, repair the damaged wire or replace the relay.

4. 4

   Replace the Motor

   If the wiring and relay are intact, the short is internal to the motor. Unbolt the defective rear wiper motor and disconnect the harness.

5. 5

   Install New Parts

   Mount the replacement rear wiper motor assembly, reconnect the electrical harness, and reinstall the plastic cover.

6. 6

   Test

   Reconnect the battery, clear the fault codes from the BCM, and test the wiper system to ensure the short circuit is resolved.