PINPOINT TEST HV: Cooling Fan Clutch: Introduction
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
To avoid the possibility of personal injury or damage to the vehicle, do not operate the engine until the fan blade has been first examined for possible cracks and separation. Failure to follow these instructions may result in personal injury or death.
NOTE:
Before starting this pinpoint test, turn the clutch fan assembly by hand and check for mechanical binding around the fan shroud or surrounding components. If binding is present, correct the problem then continue with the pinpoint test. If no binding is present, start the engine and warm up to normal operating temperature then continue with the pinpoint test.
This pinpoint test is intended to diagnose the following:
- cooling fan clutch
- harness circuits: fan speed sensor (FSS), FSS PWRGND, FSS VPWR, fan control variable (FCV), and FCV VPWR
- powertrain control module (PCM) (12A650)
| Pin | Circuit |
|---|---|
| 4 | FSS (Fan Speed Sensor) |
| 5 | PWRGND (Power Ground) |
| 2 | VBPWR (Vehicle Buffered Power) |
| 3 | VPWR (Vehicle Power) |
| 6 | FCV (Fan Control Variable) |
For PCM connector views or reference values, refer to the REFERENCE VALUES article.
| Vehicle | Pin | Circuit |
|---|---|---|
| Expedition, Navigator |
B51, B52, B53 B45 B67, B68, B69, B70 B20 B48 |
VPWR FSS PWRGND VBPWR FCV |
| F-150 | B51, B52, B53 E24 B67, B68, B69, B70 B20 B48 |
VPWR FSS PWRGND VBPWR FCV |
| All other vehicles | B35, B36 E24 B47, B48, B49, B50 E20 E7 |
VPWR FSS PWRGND VBPWR FCV |