Case IH 17589 (F-518408-06) - ECU – ECM (Engine Control Module): Power Relay driver is over loaded / over temperature only

The circuit responsible for driving the main power relay is drawing too much current or has exceeded its safe operating temperature threshold, causing the controller to log a fault to protect the circuit.

• VESTRUM CVX
• Case IH Farmall 40, 45, and 50 Tractors
• Case IH Farmall 115U Efficient Power Tractors

1. 1

   Ensure the operator is in the seat.

2. 2

   Ensure the handbrake is applied.

3. 3

   Ensure the engine speed is set appropriately as per the manual.

4. 4

   Inspect the main power relay and its socket for signs of melting, scorching, or heat damage (over-temperature).

5. 5

   Test the power relay driver circuit for a high-resistance short or an excessive amperage draw (over-loaded) that hasn't quite reached a direct short to ground.

1. 1

   Locate relay

   Locate the main Power Relay connected to the ECM.

2. 2

   Inspect relay pins

   Remove the relay and inspect the pins for corrosion or arcing, which causes high resistance and heat.

3. 3

   Test coil resistance

   Test the relay's internal coil resistance. If it is out of specification (drawing too much current), replace the relay.

4. 4

   Check wiring harness

   Check the wiring harness between the ECM and the Power Relay for chafing or partial shorts.

5. 5

   Replace or reprogram ECM

   If the relay and wiring are intact and the code persists, the ECM's internal driver may be failing, requiring ECM replacement or reprogramming.