Power window fail

[Farang]

94 Mazda B4000 V6 4.0L, promise this is my last post

Driver side power window does not work. Passenger side still works, even using driver's side button. Fuse has a metal case so I can't see if it is blown, but the two windows share the same fuse so I assume that is not the problem. Power locks on driver's side still work.

This seems to mean I definitely have to open up the door, and likely replace the lift motor. Just thought I'd run it by you guys first since I've never dealt with this before. I have a good set of instructions for performing the replacement.

 

[blahblah99]

Either the motor or driver board for the motor died.

 

[zoiks]

I'd open the button switch panel and see if you're getting current there by using a DMM. If you're not then I'd trace it back to see why you're not getting any power. If you are then the problem could be with the motor, lift mechanism etc.

 

[Pacfanweb]

It's not a fuse, it's a relay.

Here's the easy, cheating mechanic's way to diag a window that's inop:

Turn the key on, but don't start the vehicle. Look at the radio lights, or look at the volt gauge if you have one: Press the affected window's button: If the gauge twitches, or the light on the radio dims when you press the button, that's usually the window or regulator bad. Motor, most of the time.
If nothing happens, it's the switch or relay.

What is happening if the motor is bad is, it's putting a load or a draw on the electrical system, and you'll see it in the gauge. If the motor isn't even getting power, there will be no load. Meaning it's usually the switch.

 

[Mojoed]

Originally posted by: Pacfanweb
It's not a fuse, it's a relay.

Here's the easy, cheating mechanic's way to diag a window that's inop:

Turn the key on, but don't start the vehicle. Look at the radio lights, or look at the volt gauge if you have one: Press the affected window's button: If the gauge twitches, or the light on the radio dims when you press the button, that's usually the window or regulator bad. Motor, most of the time.
If nothing happens, it's the switch or relay.

What is happening if the motor is bad is, it's putting a load or a draw on the electrical system, and you'll see it in the gauge. If the motor isn't even getting power, there will be no load. Meaning it's usually the switch.

What a great post. I love good advice like this all wrapped up succinctly like this. There should be a sticky covering useful, handy tips and tricks such as this one.

 

[Farang]

Originally posted by: Pacfanweb
It's not a fuse, it's a relay.

Here's the easy, cheating mechanic's way to diag a window that's inop:

Turn the key on, but don't start the vehicle. Look at the radio lights, or look at the volt gauge if you have one: Press the affected window's button: If the gauge twitches, or the light on the radio dims when you press the button, that's usually the window or regulator bad. Motor, most of the time.
If nothing happens, it's the switch or relay.

What is happening if the motor is bad is, it's putting a load or a draw on the electrical system, and you'll see it in the gauge. If the motor isn't even getting power, there will be no load. Meaning it's usually the switch.

How about this: while doing this I didn't get any radio lights dimming (no guage), but after excessive pressing of the button I've now managed to get a bit of a squeal out of the door. A bit on again, off again, but doesn't strike me as just a slip of grip because the window never budges.

 

[LTC8K6]

If you don't use the window very often, try rapping on the motor with a small hammer.

 

[Ronstang]

Originally posted by: LTC8K6
If you don't use the window very often, try rapping on the motor with a small hammer.

My driver's side window in my 92 SHO used to stop working sometimes and when it would I just hit the bottom of the door with a rubber mallet a couple of times and it would start working again for quite some time.

 

[bruceb]

Start by trying a new switch for the driver's side window motor. Or if you have the wiring diagram for the car, check to see if the switch is getting power and if it is, is it sending power to the motor. You can also remove the connector at the switch and apply 12V to the wires that go to the motor (consult wiring diagram for which ones). Motor runs switch is bad. If it does not, most likely bad motor. But most times, you will find it is the switch that has called it quits.

 

[LTC8K6]

My driver's side window in my 92 SHO used to stop working sometimes and when it would I just hit the bottom of the door with a rubber mallet a couple of times and it would start working again for quite some time.

Oh yeah, often just slamming the door will get a Ford power window motor to start working again.