X20 - Does Fan Run With Key On

Diagnostic Trouble Code (DTC) 564 indicates a Fan Control (FC) / Low Fan Control (LFC) primary circuit failure.

Possible causes are:
- Open or shorted circuit.
- Damaged Constant Control Relay Module (CCRM).
- Damaged Powertrain Control Module (PCM).

- Does the cooling fan always run with the key on?

Yes -- Go to X24. X24 - Check FC/LFC Circuit Continuity

No -- Go to X22. X22 - Check FC/LFC Circuit For Short to Ground