Jeep 1997 Grand Cherokee Service Manual page 926

8W - 60 - 6
DESCRIPTION AND OPERATION (Continued)
For window UP operation the circuits are reversed.
The DDM powers circuit Q17 and grounds circuit
Q27.
RIGHT REAR WINDOW
Circuits Q18 and Q28 connect the Passenger's Door
Module (PDM) to the right rear window switch.
When the operator has not selected the window lock-
out feature, the PDM connects circuits Q18 and Q28
to battery voltage.
If the window is operated from right rear switch
for window DOWN operation, the switch connects cir-
cuit Q12 from the power window motor to ground on
circuit Z1. The right rear window switch connects cir-
cuit Q28 to circuit Q22. Circuit Q22 powers the win-
dow motor. Circuits Q12 and Z1 provide ground.
For window UP operation the circuits are reversed.
The right rear window switch connects Q22 to
ground on circuit Z1. Circuit Q18 from the PDM pow-
ers circuit Q12 through the closed contacts in the
right rear window switch. Circuit Q12 powers the
window motor. Circuits Q22 and Z1 provide ground.
The right rear window switch contains a Light
Emitting Diode (LED). The PDM illuminates the
LED on circuit E20.
8W - 60 POWER WINDOWS
If the operator has selected the window lock-out
feature, the Driver's Door Module signals the PDM
on the CCD bus. In response, the PDM will not sup-
ply power to the right rear window switch on circuits
Q18 and Q28. Also, the PDM does not illuminate the
LED in the switch.
If the window is operated from DRIVER'S switch
for window DOWN operation, the DDM signals the
PDM over the CCD Bus. In response, the PDM pow-
ers circuit Q28 and grounds circuit Q18. From circuit
Q28, current passes through the closed contacts in
the right rear window switch to circuit Q22. Circuit
Q22 powers the window motor. The ground path for
the motor is on circuit Q12 from the motor, through
the closed contacts in the right rear window switch to
the PDM on circuit Q18.
For window UP operation the circuits are reversed.
After the DDM signals the PDM on the CCD Bus,
the PDM powers circuit Q18 and grounds circuit
Q28.
ZG