Ultra-low voltage at power window breaker?

[chengny]

Whew!

All I could see in the quote fragment was: "chengny - you are seriously..."
I was afraid it was gonna end badly. Something like - ...f*cked up

Regardless, I apologize for the bum advice I provided you on how to jump the P/W motors. I hope you didn't waste too much time.

That's what happens when you spread yourself too thin. I was heavily into the Saab forum yesterday and also forgot the changes GM made the PW circuitry after 1981. You know, prior to that, the motors were grounded through their own casings. Just needed to provide 12VDC to one lead and the widow went up, put power to the other and it went down.


I don't know your exact situation, but it seems all you want to do at this stage is verify that the motors are good. And I also assume you are checking that the regulators and sashes are free to move throughout their full range of motion. If that is the case, there is an easier way than opening connector and running jumpers all over the place.

I just a use a battery charger set to start - or full high charge - and a pair of jumper clips. The pins on the switches - that engage the harness connectors - protrude out the back of connector sufficiently that you can clip right on there. As long as the switch is in the neutral (middle) position, no connections are being made. And so to test lowering function, you just go positive to the brown and negative to dark blue (at the visible part of the pins). Switch them to test the raise function.

The charger has to be an old-fashioned type ( the kind with no sensing of battery state of charge).

 

[da_raabi]

Success! I jumped the ground to a trim screw in the floor, applied power and ta-da!!! The windows on the truck go up and down, up and down, up and down! Just gotta get some switches, fab up a temporary/permanent ground jumper at the master switch connector and I'll be in business. chengny, thanks again for the help, you got me through this!

 

[da_raabi]

One more thing - which posts do I jumper at the main switch to get the ground pass-through for the rear windows?

 

[chengny]

Refer to the diagram below.

Remember, these are the pins to create a path to ground when driving the motor as indicated by the blue U or D. So, as in the example shown, if you were powering the left rear window in the up direction (at the local switch) you would jump pin 169 to ground (at the master switch).

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[da_raabi]

Hmm... I'm not sure if that will help then. I was hoping I could "permanently" install a jumper wire in there to bypass the front master switch for grounding. The problem is that the PO installed manual windows up front, and the master switch connector is tucked down in the door. Is there any way to do what I'm looking to do, or would I need to go get a master switch and maybe leave it down in the door?

 

[flyboy1100]

The power window modification just brings the supply voltage closer to the window controls via a pair of large wires. These are run straight from a good hot connection (the firewall junction block for example) and a dedicated ground point. Once these two wires are inside the door panel,they supply power to the motor via a relay (one for each direction).

Other than fishing the previously mentioned pair of wires (through the A pillar, rubber conduit and into the door) and mounting a pair of general purpose relays, there is not much else involved - other than a number of crimp connections to make up. Here is the most well written procedure for this modification that I have come across (the author even includes a materials list):

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dangit, more to do now!

 

[chengny]

I was hoping I could "permanently" install a jumper wire in there to bypass the front master switch for grounding.

Where do you mean by "in there"? I don't understand why you don't just pull the switch connector up and push a switch into the plug. Is it because there is no hole in the door panel?

I wish you would share your overall objective on this project. I can't figure out what we are trying to accomplish here.

Are you looking for total permanent repair & function, just testing the motors and wiring to see if it's worth fixing, only power windows in the rear and leaving the fronts as manual, etc.

Please help me out with what the master plan is?

 

[da_raabi]

Hey sorry about all of this. My end goal has kind of changed as things went along. At first I was just looking to see if the motors/system worked at all, and it does. However, the PO converted the front doors to manual, and covered over all the holes with some nice stainless trim pieces. The problem is that there is no hole in the door for a master switch now. Now that I know they work, I'd like to get the back windows fully functional. The problem now is that I cannot install a master switch - I have nowhere for it to go, unless I let it dangle down in the door. So what I am trying to do now is get the rear windows working with their regular switches, bit without the master switch. I hope that clears things up, thanks a ton for the help, and sorry for the confusion!

 

[chengny]

Just create a local ground.

Sounds like the two wires that serve dual purposes (the not pink wire) will never be used again - to send a remote positive signal from the driver master switch. Consequently, they can be made into dedicated ground wires.

Cut them both near where they enter the door. Splice them together, add an extension and run that new single lead to a good clean ground point. Since your truck is older, the hinges are probably metal to metal by now - so you'll probably be alright if you use a screw somewhere on the door shell. There should be continuity through the hinges and into the frame.

In the end you will have power into the switch on the pink wire. The switch will control the polarity through the motor and your new leads will create a path to ground. In the dwg below, red indicates positive and blue indicates negative.:

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[da_raabi]

Total success! I grounded the four "master switch" wires using a nice little harness the wifey made, and ta-da! Working windows! Chengny - again you are the bomb. Seriously this project has been a PITA, but you got me through it! Now I just need to clean up the window mechanisms a bit and I should be good to go. It sure was nice having 3 windows open on the way to work this morning! (The fourth needs new window sweeps - the old ones are hanging up the window). Thanks again!