Case IH 520561-05 - BCM – BCM: Rear Windshield Washer Motor Circuit - Current Below Normal or Open Circuit

The control module is attempting to send voltage to the rear windshield washer motor/pump, but it is not detecting the expected electrical current returning through the circuit. This indicates a physical break in the circuit, such as a disconnected plug, a severed wire, a blown fuse, or a burned-out internal winding inside the washer motor itself.

• MAGNUM AFS Connect
• Magnum
• Puma
• Maxxum
• Optum
• Steiger
• Axial-Flow

1. 1

   Check the cab fuse panel for a blown fuse or faulty relay assigned to the rear washer/wiper system.

2. 2

   Visually inspect the wiring harness leading to the rear washer fluid reservoir for rubbed-through wires, rodent damage, or a disconnected plug.

3. 3

   Unplug the connector at the washer motor and inspect the pins for severe corrosion, moisture intrusion, or pushed-out pins.

4. 4

   Perform a voltage and ground test on the harness side of the connector using a multimeter. Have an assistant press the rear washer switch in the cab to verify 12V on the power wire and good continuity to ground.

5. 5

   Test motor continuity by measuring the resistance (Ohms) across the two terminals on the washer motor. If the multimeter reads 'OL' (Open Loop) or infinite resistance, the motor's internal windings are broken.

1. 1

   Prep the Area

   Turn off the tractor ignition and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Access the Motor

   Locate the rear washer fluid reservoir. The washer motor (pump) is typically press-fit into a rubber grommet at the lowest point of the reservoir.

3. 3

   Drain the Fluid

   Place a clean catch pan under the reservoir. Disconnect the rubber fluid hose from the motor nipple and allow the washer fluid to drain.

4. 4

   Remove the Motor

   Disconnect the electrical pigtail. Firmly grasp the washer motor and pull it straight out of the reservoir grommet.

5. 5

   Inspect the Seal

   Remove the old rubber grommet from the reservoir hole. Clean the sealing surface. If the new motor did not come with a grommet, inspect the old one for tears (though replacing it is highly recommended to prevent leaks).

6. 6

   Install the New Motor

   Lubricate the new rubber grommet with a small amount of soapy water and press it into the reservoir. Push the new washer motor firmly into the grommet until it seats fully.

7. 7

   Reconnect

   Reattach the fluid hose to the motor nipple and plug in the electrical connector.

8. 8

   Test

   Refill the reservoir with washer fluid. Reconnect the battery. Turn the key to the ON position and activate the rear washer switch to prime the pump and verify operation.

9. 9

   Clear Codes

   The BCM may require the fault code to be cleared via the tractor's display monitor or a diagnostic scan tool, though some models will move the code to 'Inactive' history once the circuit is restored.