I have a 1998 Ford Taurus and a compound electrical issue. The door
ajar light is on most of the time but sometimes goes off and the
instrument illumination lights dont work. Are these two related? If
so, where would you start to look? The side mirrors dot work and the
driver side rear window also dont work.
I would check ALL the grounds under the hood, including to the firewall,
battery cables, and battery to block. (clean and retorque as necessary.
Then you need to find where the under the dash grounds are and do the
same. Not sure where then are on a gen 3.
Bob makes a good point about the grounds. They can cause a lot of
strange electrical issues. Certainly check them.
In my experience with Ford products in general these problems are
usually unrelated, although I've seen them all on the same vehicle at
the same time.
Here's what I would do first:
Door Ajar Light- usually the pin switch in one of the door latches
sticks. You'll also notice that the interior lights may stay on for a
long time after you exit the car, about 10 minutes IIRC. Flood the
door latches with WD-40 into any crevice the tube will fit into. Aim
high, the switch is in the door latch, above the "jaw" area. Then open
and close the door about 20 times. The light should go off. Follow up
with a shot of white lube (spray lithium grease) in the latches. If
the problem returns, one of the switches will need to be replaced. An
electrical manual and testing is needed to determine which one.
Left Rear Window- The motor gets "stuck" from non-use or is damaged
from kids holding the button in the UP position way too long. Turn the
ignition switch on and watch the dome light. Push the window switch to
the down position. If the dome light dims just slightly, the motor is
"stuck". You may have to do it a few times to really see the dimming.
If so, open the door and stand between the door and the car. Push the
switch to the Down position and smack the interior panel below the
grab handle (toward the bottom of the door) with a rubber mallet, or
the side of your fist if you're tough, really hard a couple of times.
The window will probably go down and work fine for a while. It will
"stick" again eventually so a new window motor is in order soon. (bad
spot on the commutator).
If you don't get the "dimming" then further testing is needed. You;ll
need the electrical manual. (If it dims UP,and not DOWN, the switch is
Note: I'm not questioning your intelligence, but I've seen a lot of
cases where the user isn't familiar with how the controls work on
their car. For the mirrors and inst, panel lights, make sure you know
how the controls work. (Again, I only point this out because I've
seen it very many times).
For the mirrors you twist the knob left or right to adjust the
For the Inst. Panel Lamps, the dimmer is a thumbwheel to the right of
the headlight switch. Roll it upward to brighten the lamps.
Outside Mirrors- (Make sure you are twisting the mirror knob Left or
Right to adjust the left or right mirrors respectively, center is OFF)
The biggest culprit is the mirror switch itself. If neither mirror
will work in any direction, turn the L/R switch from left to right
about 20 times then try it. If the mirrors work now, cool. When the
switch stays in the centered position for a long time, the contacts
may not conduct well. If not, you'll need to do some more testing and
an electrical manual is necessary. (the switch is probably bad)
Inst. Panel Lights-(Make sure the dimmer control is turned all the
way up) Check the fuse first and foremost. Is there any aftermarket
electronics installed on the car (Radio, lights, etc)? If so, the
wiring to the aftermarket things is suspect. If no aftermarket stuff
and the fuses are good, the dimmer control for the lights is the usual
The radio display should light up bright with the park/head lights
OFF and dim slightly with the lights ON. If the radio goes blank with
the lights ON, check the dimmer control setting and the fuse. If
that's not the problem, guess what? Yep, further testing is needed.
I hope this helps.
Thanks Bob and Tom
I got everything lined out except the dimmer but I really want to wait
til dark to be sure. The light in the ashtray is in the same circuit I
beleive and it does not illuminate but the bulb looks good. With the
dimer switch all the way up there is a switch that turns on the dome
light. Does that indicate that the dimmer switch is good? I know it is
a potentiometer but in the full position and the dome light working
that seems to indicate there is a closed circuit. Are they 2 separate
If I remember right, the inst panel lamps are supplied by the park
lamp circuit through a separate 3(?) amp fuse. Check for power to that
fuse with the lights on. If there is power to the fuse, work toward
If no power at the fuse, make sure the park lamps work and look in
the direction of the headlamp switch.
The switch for the dome lamps is part of the dimmer but entirely
Was I anywhere close on the other issues? Just curious.
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