Case IH 518150-05 - BCM – BCM: Electrical crank power relay - open circuit

Indicates an open circuit in the electrical crank power relay, meaning a break in the electrical path such as broken or disconnected wiring, or an internal failure within the relay itself preventing current flow.

• MAGNUM AFS Connect
• Magnum series tractors
• Puma series tractors

1. 1

   Check for broken, disconnected, or damaged wiring in the harness leading to the crank power relay

2. 2

   Check for an open circuit inside the relay itself by testing for continuity across the relay coil

3. 3

   Verify if the module is outputting the correct voltage to the relay circuit

4. 4

   Erase the fault code from memory and attempt to operate/crank the vehicle to see if the error actively reappears

1. 1

   Locate the relay

   Locate the electrical crank power relay (often referred to as the starter motor relay on the low side of the circuit).

2. 2

   Repair or replace wiring

   If the wiring harness is broken or disconnected, repair the wiring defect or replace the affected harness section.

3. 3

   Replace the relay

   If the relay fails a continuity test (internal open circuit), remove and replace the relay.

4. 4

   Address potential BCM/ECU failure

   If the wiring and relay are intact but the code persists, the issue may be an internal BCM/ECU failure requiring module replacement or calibration. Contact Helpdesk for internal ECU failures.