Question on pw switch operation - 2000obw

[Steves72]

I likely have a failed switch for my rear driver window. Most likely it is probably the driver switch but does anyone know if the failure of one switch will cause the window to not operate from either power window switch? Is there any type of relay bewtween the switch and the motor?Neither the driver switch nor the rear door switch will raise the window.

 

Steve

[ericem]

Hmm i wonder the same, but might be the motor, because i beleive each button gets there own 12v or does one switch get the 12v? no im pretty sure it the motor if both switches dont work. Relay good question.

[nipper]

all power goes through the master switch. Thats why you can lock out all the other windows. Your going to have to check and see if there is power to the rear switch from the front master switch. Also check the motor for any opens. The switches can be taken apart and cleaned if your careful.

 

nipper

[OB99W]

I likely have a failed switch for my rear driver window. Most likely it is probably the driver switch but does anyone know if the failure of one switch will cause the window to not operate from either power window switch? Is there any type of relay bewtween the switch and the motor?Neither the driver switch nor the rear door switch will raise the window.

 

Steve

I looked at the wiring diagram; the motor for the left rear window is wired directly to the switch in its door. Naturally, the switches are set up so that either the main (driver's) switch or the passenger's one can operate the motor in either direction, but they can't "fight" each other. With neither the main nor the passengers switch being operated, the motor has both of its leads grounded. If one of the switches is actuated, one motor lead is grounded and the other is connected to hot; the polarity depends on the direction selected. If the driver and passenger simultaneously select opposite directions, the motor stops, because both motor leads are made hot (and neither is grounded !). The switching/wiring needed to accomplish all of that means a problem with either switch (or wiring between them) can result in neither being able to operate the motor.

 

 

all power goes through the master switch. Thats why you can lock out all the other windows.[...]

Sorry nipper, but assuming the daigrams I have are correct, I have to disagree with that part. The diagram for the 2000 doesn't show a lock-out switch. The '99 has one, and it locks out operation of all the windows except the driver's, not only at the individual passenger positions, but at the main (driver's) location as well. It does that by interrupting the ground connection, not the hot lead.

[nipper]

the 2000 doesnt have a lockout switch?

 

nipper

[J A Blazer]

My 2000 OBW has one.

[OB99W]

the 2000 doesnt have a lockout switch?

My 2000 OBW has one.

That's why I brought up the issue of the correctness of the diagram, since from a safety standpoint not having the switch didn't make sense.

 

However, I stand by the fact (at least on the '99) that the lockout is done by breaking the ground connection to the switches, not the hot lead. Hot power does go directly to the three "sub" switches, in addition to the main switch at the driver's location, on both the '99 and '00.

[Steves72]

After removing the rear door panel I found a heavier wire pair heading in the direction of the window motor. It was wrapped in a white sheathing and had a green connector. I unplugged this connector and used a battery charger to get the window back up. On my first try the polarity was wrong and the motor tried to lower the window but it was already fully down. I reversed the polarity and the window went up.

 

Now that the motor being bad can be ruled out, it seemed most likely that the problem would be a switch. But something must be in between the switch and the motor to cut power to the motor once the window has reached full up or full down. That was why I asked if there was some type of relay in the system. I still believe that it is the driver window switch that failed since that gets used the most.

 

I wish I had that wiring diagram.

 

Steve

[Steves72]

If I do nave to replace the driver door switch; does anyone know how much that part costs?

 

I recently had to replace the same item on my wife's 99 Grand Prix. On her car the pw switch for the driver's door is a unit that comprises all four switches and the lock out button. The dealer wanted around $100 for it.

 

Steve

[ferret]

Here's 1 page from the FSM. Disregard if you don't have illuminated switches.

 

As you can see +12 goes to both the front and rear switches. But the ground return only thru the front main switch. From the motor, thru the rear switch ( whether activated or not ) to the front main switch (whether activated or not ).

So no matter which switch you attempt to use, the ground returns thru both switches. So either can cause the window not to operate.

[OB99W]

[...]Now that the motor being bad can be ruled out, it seemed most likely that the problem would be a switch. But something must be in between the switch and the motor to cut power to the motor once the window has reached full up or full down. That was why I asked if there was some type of relay in the system. I still believe that it is the driver window switch that failed since that gets used the most.

 

I wish I had that wiring diagram.

There is a relay (so that the ignition switch doesn't have to handle all the current), and a circuit breaker (for protection). They affect the entire system, and neither would cause a problem at just one window. Typically power window motion is limited by the regulator; if you don't let go of a switch at the end of travel, eventually the excessive current causes the breaker to snap open. It's usually a thermal (bimetallic) kind, and will reset by itself after a while.

 

Check your Private Messages.

[Steves72]

Sounds like it will be the switch. I will try cleaning both. Thanks.

Steve