Operation CHARM: Car repair manuals for everyone.

X19 - Check HFC Circuit For Shorts To Ground



- Key "OFF".

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

- Constant Control Relay Module (CCRM) disconnected.

- Measure resistance between the High Fan Control (HFC) test pin and test pin 40 at the breakout box.

- 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 to ground in HFC circuit. Remove breakout box. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)