X85 - Check For Intermittent Open or Short to Power

- Scan Tool connected.

- Key On, Engine Off.

- A/C off.

- Cooling fan must be off.

- Access FANM PID.

WARNING: STAY AWAY FROM THE COOLING FAN BLADES WHILE PERFORMING THIS TEST STEP. THE COOLING FAN MAY COME ON.

- Observe Scan Tool for an indication of a fault while performing the following (a fault will be indicated by the FANM PID turning ON):
- Shake, wiggle, bend the Power-to-(Low Speed) Fan circuit between the CCRM and the cooling fan.
- Shake, wiggle, bend the cooling fan ground circuit.
- Lightly tap on the cooling fan and CCRM to simulate road shock.
- Shake, wiggle, bend the FANM circuit between the PCM and splice.

- Disconnect the cooling fan and CCRM. Inspect the connectors for corrosion, damaged pins, etc.

- Key Off.

- Was a fault indicated?

YES -- If the cooling fan turned on when the fault was detected, a short to power exists. If the fan did not come on, check for an open circuit. ISOLATE fault and SERVICE as necessary. RECONNECT all components. Complete PCM reset to clear DTCs. Clearing Diagnostic Trouble Codes

Rerun quick test. Diagnostic Subroutines (DSR) - Extracting Codes

NO -- GO to Pinpoint Test Step Z1 with the following data: FANM, FCA/LFCA and HFCA PIDs (to verify that the fan is commanded off during testing) and list of Possible Causes. Z1 - Intermittent Test Procedure