KF6 - Check LFC/HFC Circuit For Short to Ground

- Key "OFF".

- Breakout box installed, Powertrain Control Module (PCM) disconnected.

- Low Fan Control (LFC) or High Fan Control (HFC) relay disconnected.

- Measure resistance between applicable test pin (LFC or HFC) and test pins 40 and 60 at the breakout box.

563 / HFC pin 31
564 / LFC pin 13


- Is resistance greater than 10,000 ohms?

Yes -- Replace PCM. Remove breakout box. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Service short circuit. Remove breakout box. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)