I have a '94 Aerostar, 4.0 L, 2WD, with power windows. The passenger window goes down but not up. Does anyone have a simple solution? Could it just be the switch or is it more likely the motor? Thanks for any help.

 

Sounds like the switch. They are flimsy, and when the plastic breaks or cracks on the top or bottom (in your case the top) where it attaches to the tab on either side of the switch the window will move one way but not the other. I paid $1.99 for my driver side switch at the junk yard, so I would try that first. Take out the switch (takes about 2 minutes) and check it. Good chance it's broken.

 

Thanks Scott9050. That does seem (and hopefully is) the most logical explanation. I don't see any cracks or breaks but I know that there is power to the switch. At the same time, it doesn't sound right that there's a problem with the motor if it wound down without a problem. I'll try finding a replacement tomorrow and see what happens.

 

Will the window work from the driver's side but not the passenger side? Or the other way around? or neither?

It could be the switch. But then again. It could be a broken wire between the two doors. That could cause the same problem.

There are three wires that go to the passenger's door switch. Two of them come from the driver's door switch. One is the power. It is hot (12VDC) with the key on. The other two (from the driver's door) are both grounded without the driver's switch being pressed.

Pressing the up or down for the right door (on the left door switch) will cause one wire to go hot while the other stays at ground.

Tell me how the switches act and I'll give you a better guess as to what the problem is.

By the way pressing up on the driver's switch will cause the R/BK wire to go hot on the passenger's switch. Pressing up on the other switch will cause the R/Y wire to the motor to go hot.

 

Hi Tom,
Well, I've just finished dismantling the switch, cleaning inside and reassembling (some glue required). Still the same problem. There is no response either up or down from the driver's switch (for the passenger window) and only the down response from the passenger's switch. The driver's window operates up and down, no problem.

 

Sorry, I didn't completely answer your query re: the hot wires. I will check in a short while to see if there is any current passing from the left to the right door as you have described.

 

OKay Tom, Here's what happens with the wires on the switch. As you know there are 3 on one side, two on the other which I'll call 1, 2, 3, 4, 5.

1 is ALWAYS hot or live when the engine is running.

With the Driver's Side Passenger Window switch UP - wires 2, 4, 5 are hot. With the DSPW switch DOWN - none are hot (except 1 of course).

With the Passenger's Side Window switch UP - wires 2, 3, 5 are hot. With the PSW switch DOWN - wire 2 is hot; wires 4 and 5 have a faint 2VDC current.

Does that make any sense?

 

It does make sence. Sort of. It would help if you had used the color wire instead of numbers. Let me approach it from the other direction.

There are five wires on the right door switch.

LB/BK is hot with the key on. Your number 1.
W/Y comes from left door switch (2) my number
T/LB comes from left door switch (3) my number
Y/R goes to the window motor (4) my number
R/Y goes to the window motor (5) my number

I suspect you have a problem between the two doors. Here is why.

When the switch is not pressed on the left door switch there should be continuiety to ground on both 2 and 3.

Pressing the left door switch up will cause 3 to go hot. This will give you hot at 3 and 5 down to the motor. There should be a gound on 2 that goes down 4 to the motor. If the ground is not there then 4 will float up to 12VDC. So if 2 is at 12VDC, it too is floating. That means you do not have a ground from the left door. If 2 is at ground then you have a switch problem in the right door.

Now if the left door switch is press down, There should be 12 VDC on 2 and there is not. This could be a bad wire from the left switch.

So it looks like a problem with the W/Y wire from the left door switch. It could be a broken wire or a bad left switch. If this is the case it would cause the right switch to work lowering the window but not raising it.

Try measuring it again and let me know the results using the color instead of the number.

 

Tom,
This is the color configuration on my passenger side window switch.

When I remove the side panel cover, pull out the switch assembly and flip it over, I have 3 wires on the left side of the switch and 2 wires on the right side.

Starting at the top of the 3 wires (the ones I referred to as 1, 2, 3 before), the colors are LB/BK (hot), R/Y, and T/LB.

On the right side the 2 wires starting at the top again (what I called 4, 5 before) are W/Y and Y/R.

Just to be sure we're referring to the same color coding, I'm using "main color/stripe", e.g. LB/BK, in the case of the hot wire means a Blue wire with a Black stripe and so on.

So, to match up my earlier number reference with the colors - 1 = LB/BK; 2 = R/Y; 3 = T/LB; 4 = W/Y; 5 = Y/R.

The earlier measurements remain the same when taken again. However, let me say that I was able to jump two of the wires together with the switch in the up position to close the window. (I think it was LB/BK & Y/R that when connected by a small jumper wire caused the window to go up.) Thank goodness as the temperature is well below zero centrigrade here.

At least my family won't freeze until I can sort this out. Not an easy task as access inside the door is very limited.

 

OK, We're getting closer. I still think we have some numbers crossed or something.

I think the problem lies with the W/Y wire. Let me restate you numbers to make sure we have them correct.

1 LB/BK (HOT)
2 R/Y to window motor
3 T/LB to left door switch
4 W/Y to left door switch
5. Y/R to window motor

The two (3 & 4) wires come from the left door switch. Both are grounded normally. Pressing up on the left door switch causes 3 to go hot and 4 to stay grounded. If 4 is open/broken, then the window will not open. Pins 1, 2, and 3 will be hot. Pin 5 will float to 12VDC. You stated it is 1,2,4, and 5. Could it be 3 not 4?

Pressing down on the left door switch causes 4 to hot while 3 is grounded. You should have 12 VDC on 1,4, and 5. Since you don't have anything hot but pin 1, I still say the problem is with pin 4 the W/Y wire.

Given no connection between pin 4 and the left door switch, what will happen using the right switch?

1 Pressing up will cause pin 2 to go hot. If pin 4 is open, pins 4 and 5 will float up to 12 VDC. So pins 1,2,4, and 5 will be hot.
2 Pressing down will cause pin 5 to go hot and while pin 3 is grounded. This will cause the window to go down. Which it does.

My best guess at this point is a bad connection between the two switches. There is a Y/BK wire that connects to the left door switch that comes over to the right door switch (now it's W/Y). This wire is normally grounded until the switch is pressed. It goes hot when press down and is grounded when press up or not pressed. So the problem could be a bad left door switch or a broken wire.

 

Thank you so much for your kind advice Tom. I'll be able to spend more time checking all the wires, contacts, grounds, etc., as the weather warms up towards the weekend. A heated garage would be nice. I'll have to hunt around for a vacant workspace to call my own.