XB30 - KOEO Code 582: Verify Cooling Fan Is Not Always On

Key On Engine Off (KOEO) Diagnostic Trouble Code (DTC) 582 indicates an open or short to power in the power-to-cooling fan circuit.

Possible causes:
- Open or short to power in the power-to-cooling fan circuit (harness).
- Open cooling fan motor ground circuit.
- Open circuit in cooling fan.
- Damaged Variable Control Relay Module (VCRM).

NOTE: If KOEO DTC 587 is also present, refer to the EEC-IV DTC charts to address the 587 first. Also verify that the cooling fan was not turning during KOEO Self-Test. If the fan was turning, back voltage could be sent to the VCRM through the power-to-cooling fan circuit resulting in an invalid 582 DTC.

- Engine cooled down (so cooling fan would normally be off).

- A/C and defroster "OFF".

- Key "ON", engine "OFF".

- Is cooling fan on?

Yes -- Key "OFF". Go to XB35 (to check for short to power). XB35 - Check Power to Cooling Fan Circuit For Short to Power

No -- Key "OFF". Go to XB31 (to check for opens). XB31 - Check For Voltage to Cooling Fan