X22 - Check FC/LFC Circuit For Short to Ground
- Key "OFF".
- Disconnect Powertrain Control Module (PCM). Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.
- Install breakout box, leave PCM disconnected.
- Disconnect Constant Control Relay Module (CCRM).
- Measure resistance between test pin 13 and test pins 40/60 at the breakout box.
- Is resistance greater than 10,000 ohms?
Yes -- Go to X23. X23 - Check Fan Running Mode
No -- Service short to ground in Fan Control (FC) / Low Fan Control (LFC) circuit. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)