Power Window Circuit Description and Diagnosis
Bruce Glad writes
My right side front door window came out of the track resulting in it
jamming. After a few cycles of trying to free it up by alternate up and
down selections on the switch, something clicked and there was no more
power to the switch. I have succeeded in reinstalling the window in its
track, but not in getting power back to the switch so I can close the
window. There are no blown fuses in the fuse block in the passenger side
footwell, the driver side footwell, or the auxiliary fuse block under
the hood on the left side of the engine compartment, nor is the in-line
fuse by the battery blown. There is continuity between ground on the car
and the ground terminals in the connector to the switch. Threre is no
+12v on the connector to the switch at any terminal. The right side rear
window worked before this incident and does not afterward. It's switch
connector also has continuity to ground at the proper places, but no
+12v. The left side windows work fine, as does the sunroof. What am I
missing? Thanks to any who can enlighten me.
The Series III power window and sunroof circuit is protected by two
One breaker protects the left side windows and sunroof circuit, the
other breaker protects the right side window circuit. Your circuit
obviously got too hot and tripped the breaker. The breakers and the
relay are located at the right hand component panel. The relay round and
at the extreme right side of the panel. The breakers are square, with
two terminals on top, and mounted lower on the panel.
Here's a circuit description and diagnostic quick-reference:
White/pink wire at relay terminal 85 -- voltage with key "on"
Brown wire at relay termianl 30/51 -- voltage at all times
Red/slate wires at relay teminal 87 -- voltage with key "on"
Black wire at relay terminal 86 -- ground through
Note that the lock-out function (through the console switch) operates by
removing the ground to the relay, thus rendering the relay inoperative.
The red/slate wires are output to the switches. From the relay the wires
go to the two breakers. With the key "on" verify that voltage is present
on both sides of the breakers. If not, the breaker is "open" and that
portion of the circuit won't work.
The relay terminals should be checked for cleanliness and security as
many problems can
solved with a few minutes attention here.
If the circuit appears to be fundamentally in order but a window or
windows don't operate it is very likely that the switch is faulty. In
nearly all cases the switch contacts are simply dirty. After removing
the console cubby box and the plug-in at the rear of the switch, the
switch can be pushed out through the console after squeezing the tabs on
Many owners sucessfully disassemble the switch (keep track of all the
bits !) and clean the contacts with a pencil eraser or contact cleaner.
Many others report good results by simply
spraying liberal amounts of aerosol electrical contact cleaner through
the small holes in the switch casing.
This circuit, by the way, is not fused.