Mark VII V8-302 5.0L VIN F FI (1987)
FIGURE 1 - Wiring Diagram, Heated Rear Window
TESTING
Control Assembly Tests
1.
Ground pin 2 and connect a jumper wire between pins 4 and 3. Connect a 12-volt test lamp between pin 1 and ground (Fig. 1).
2.
Apply power to pin 4. The test lamp should not light.
3.
Momentarily actuate the lever to the ON position. The test lamp should come on and stay on after the lever returns to the normal position.
4.
Test lamp should go off under any one or more of the following conditions:
^
If lever is moved to the OFF position.
^
Jumper wire between pins 3 and 4 is removed.
^
Approximately 10 minutes has elapsed.
1988 Lincoln Town Car - Ford (Crown Victoria) - Mercury (Grand Marquis)
36-86-2
Window, Rear-Defroster
36-86-2
Grid Wire Test
1.
Using a strong lamp inside the vehicle, visually inspect the wire grid from the outside. A broken grid wire will appear as a brown spot.
2.
Run the engine at idle. Set the control switch to ON. The indicator lamp should come on.
3.
Working inside the vehicle with a 12-volt DC voltmeter such as Rotunda Digital Volt Ohm Meter 007-00001 or equivalent, contact the broad
redbrown strips on the rear window (positive lead to battery side and negative lead to ground side). The meter should read 10-13 volts. A lower
voltage reading indicates a loose ground wire (pigtail) connection at the ground side of the glass.
4.
Contact a good ground point with the negative lead of the meter. The voltage reading should not change.
5.
With the negative lead of the meter grounded, touch each grid line of the heated rear window at its midpoint with the positive lead. A reading of
approximately 6-volts indicates that the line is good. A reading of zero volts indicates that the line is broken between the midpoint and the B+ side
of the grid line. A reading of 12-volts indicates that the circuit is broken between the midpoint of the grid line and ground.
