Case IH 522833-03 - PCM – PCM: Remote output short circuit to battery or overvoltage

The control module has detected that the voltage on its remote/auxiliary output circuit is abnormally high, or the circuit has physically shorted to a 12V power source (battery voltage).

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect series
• Case IH Steiger / Quadtrac AFS Connect
• Case IH Puma AFS Connect
• Case IH Optum AFS Connect

1. 1

   Verify the tractor's overall system voltage by testing the alternator output to ensure the voltage regulator has not failed, causing a machine-wide overvoltage condition.

2. 2

   Visually inspect the wiring harness running from the PCM to the remote/auxiliary output connections for chafed insulation, melted wires, or pinched areas touching a 12V power supply.

3. 3

   Disconnect the accessory connected to the PCM's remote output and use a multimeter to check for voltage on the harness side of the output pin when the circuit is commanded off.

4. 4

   Check the disconnected accessory for internal shorts that might be feeding voltage back into the PCM.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the negative battery cable to prevent electrical damage during repairs.

2. 2

   Repair the Harness

   If the diagnostic checks revealed a short to battery in the wiring, locate the damaged section of the harness. Splice and solder in new wire, and seal it with heat-shrink tubing, or replace the affected harness section entirely.

3. 3

   Replace the Accessory

   If the remote device/accessory was found to be internally shorted to power, replace the component.

4. 4

   Replace the PCM

   If the wiring harness and external components are perfectly intact but the PCM continues to register an internal short to battery on that output, the PCM's internal driver has likely failed. Replace the PCM.

5. 5

   Reassemble and Clear Codes

   Reconnect the battery, turn the key on, and use the AFS Pro 1200 display or a DPA5 diagnostic tool (Type 2 green connector for AFS Connect models) to clear the fault codes. Test the remote output to ensure the code does not return.