CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Rear window switch questions

apache

1/2 ton status
Joined
Nov 2, 2008
Posts
314
Reaction score
0
Location
Central coast of Kali
My 84`s rear window key switch on the tailgate is dead and Id love to be able to have a way to open it from outside the truck so.... Is it the key switch that takes a dump typically or ? I have also considered option #2 which is at this point Im willing to rewire the entire window motor battery direct with bigger wires,and nneded protection to a hidden switch out back somewhere but have no clue as to which wire does what off the motor to make a new harness.
Any ideas?
 
The way the rear windows work is a bit different. They don't switch the ground, they switch hot from the front switch, and the key switch makes contact with different connectors and then supplies voltage to the motor. So all three wires running into the tailgate are actually hot wires, the ground is provided through the tailgate.

I can't remember the colors off hand, but one wire comes from the dash switch with + to run up, the other does + to run down, and the third wire is constant + for the key switch in the gate. The contacts can become corroded enough in the switch to prevent the lowering or raising of the window, especially if the weatherstrip leaks anywhere.

You didn't say if the window works off the dash switch, but if it does you should be able to see what the wire colors are there, then the third wire will be the constant. Make sure this wire is providing power to the switch, and if it is the switch is bad. If it is not sending power back, then there is most likely a break in the wire and that is why your key switch is not working.
 
Yes, the dash switch works, and makes sense on the hot wire up and hot wire down but then the single hot to the key switch and it allows the window to go either way?
BTW,thank you for the info.
 
As long yuo have power into the tailgate, then your okay the rest is easy.

You will have to remove the cover, window etc to get to the electic part. The "lobe" which is the best way to describe it wears out, and does not contact the up or down terminals.

I *think* you can get it at a parts store, or LMC. When I did mine, going in blind I think it took me 1/2 hour to get done? Works like a charm now.
 
Only the two wires to the dash switch are keyed, the other to the tailgate switch is constant hot. It works by making contact with different copper contacts in the switch, one for up, one for down. Most likely, if you have constant power back there, the switch itself is the culprit.
 
The switches are rebuildable in most cases. Simply clean the copper off, coat with dielectric grease, and reassemble.

Of course, if the copper is corroded through, get a new one.
 
Good info here. I too have a key which does not move the window. Just recently the front switch stopped working as well.

The window went down, but the motor was "clicking" when I tried to put it back up. First I disconnected the sleeve cable from the motor, was able to verify the motor turned in the "down" position.

Fiddled with the connections a bit and now it clicks for both up/down.

I've seen the other posts about the safety switch on the driver's side latch, will try to bypass that first and see where it takes me.

Other posts about the back window have mentioned faster motoring when upgrading the ground wire to 10 guage. Anybody on this thread tried with success?

Plus does anybody here know where these power lines run thru the firewall into the passenger compartment? The corrugated tubing on my wires has fallen away to dust, and I need to run new wires from front to back (they are cracking). Any suggestions on a good upgrade path for the wires?
 
Isn't the setup grounded right at the tailgate, either to the frame or to the gate itself? If so, I'd expect changing ground wire to larger would do little, EXCEPT that if the wire/connection is bad already, it would certainly make it better, but not due to size of wiring.

I think the power lines run through the engine side of the fuse panel, but I could be mistaken.
 
Isn't the setup grounded right at the tailgate, either to the frame or to the gate itself? If so, I'd expect changing ground wire to larger would do little, EXCEPT that if the wire/connection is bad already, it would certainly make it better, but not due to size of wiring.

yes, a small (looks like 14ga) ground attaching the motor to the tailgate itself, maybe 7-8" total length. Didn't look physically banged up, but who knows after 18 years.

I think the power lines run through the engine side of the fuse panel, but I could be mistaken.

I'd prefer not to leave these wires bare, but not sure what I could wrap them in aside from electrical tape (which I really don't want to do). heh, I wonder if conduit would work. :D
 
Here's what I found with mine, something else for you to look for...

3 wires go into the tailgate. 2 of those wires are then split into 2 again via crappy factory splice and tape. At both of those splices I found that moisture had gotten through the tape and corroded the splice connections. Just had to cut the wires back and make new connections and seal them up better than the factory did. Works wicked pissa now. Not saying this is your particular problem just something to check while your in there.
 
You can still buy the convoluted tubing at many places. Just a quick online search first result:
http://www.nelcoproducts.com/shopping/shopexd.asp?pid=624&cid=106

I've seen it at chain auto parts stores, but no idea if its worse quality than what GM used.

Important thing with wiring is to keep it as far away from heat as possible, physically protect it, and secure it so that abrasion is a non-issue.
 

Latest Posts

Top Bottom