1989 pontiac trans am GTA rear window defrost
#1
1989 pontiac trans am GTA rear window defrost
hi guys, need help with rear window defrost.
i changed rear trunk holders and put back all wires, but now when i sit in car and push button to switch on rear window defrost all cars electricity just tears up for one the moment when i push button
it feels like it going interconnection, any ides what could be the problem?
i changed rear trunk holders and put back all wires, but now when i sit in car and push button to switch on rear window defrost all cars electricity just tears up for one the moment when i push button
it feels like it going interconnection, any ides what could be the problem?
#2
Re: 1989 pontiac trans am GTA rear window defrost
hi guys, need help with rear window defrost.
i changed rear trunk holders and put back all wires, but now when i sit in car and push button to switch on rear window defrost all cars electricity just tears up for one the moment when i push button
it feels like it going interconnection, any ides what could be the problem?
i changed rear trunk holders and put back all wires, but now when i sit in car and push button to switch on rear window defrost all cars electricity just tears up for one the moment when i push button
it feels like it going interconnection, any ides what could be the problem?
"all cars electricity just tears up for one the moment when I push button"
can be translated to ;
"When I push the rear defroster button , all of the car's electrical devices stop working" ?
If yes , you have a short circuit in your new "trunk holders" (lift cylinders) and this must be rectified before you push the button even once more , lest you fry a fusable link (In reality , you should have already fried one) .
I have read about certain lift cylinders being manufactured without the required electrical insulation to keep the defogger's power from shorting to ground . I believe there was a discussion thread somewhere here at TGO that detailed the problem , I remember reading it but didn't pay it too much attention because my car wasn't equipped with the rear defroster .
#3
Re: 1989 pontiac trans am GTA rear window defrost
hi, but its the problem could be with lift cylinders (production fail) or problem is with installation?
because putting them in is straight forward two buttons and thats it.
because putting them in is straight forward two buttons and thats it.
#4
Re: 1989 pontiac trans am GTA rear window defrost
Elmars , I don't think it's the installation , I think it's some plastic insulation that's missing from the new lift cylinders . If you do a search here you should (eventually) find the thread I read about the short circuiting lift cylinders which mentioned some plastic missing from the new units .
#5
Re: 1989 pontiac trans am GTA rear window defrost
went today to garage and tested all...
i put in the old lifters and tested the rear defroster and it worked perfect no problem.
than i put in the new lifters and when i push the button it goes to short cut...
than i tested all lifters and the problem is that it dosnt isolate holding bolts.
the difference between old and new is that if you put bolt in how holds the the lift,
that in old ones the lift is isolated form bolt and dont put electricity to body, but new lift
dosnt isolate bolt so thats why it makes shorcut... now need to think what to do...
i put in the old lifters and tested the rear defroster and it worked perfect no problem.
than i put in the new lifters and when i push the button it goes to short cut...
than i tested all lifters and the problem is that it dosnt isolate holding bolts.
the difference between old and new is that if you put bolt in how holds the the lift,
that in old ones the lift is isolated form bolt and dont put electricity to body, but new lift
dosnt isolate bolt so thats why it makes shorcut... now need to think what to do...
#7
Re: 1989 pontiac trans am GTA rear window defrost
i tested that dosnt help, because when you put bolt through than bolt touches in the middle also and that gives short cut, so if i isolates the bolt head bolt touches lift in the middle and that gives shortcut ..
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Re: 1989 pontiac trans am GTA rear window defrost
You need to move the plastic bushings/grommets to the new struts. The struts need to be electrically isolated from the body of the car. At least one of them does, the one carrying the +12 volts.
If the OEM bushings/grommets don't fit the new struts then they are not correct (junk).
RBob.
If the OEM bushings/grommets don't fit the new struts then they are not correct (junk).
RBob.
#9
Re: 1989 pontiac trans am GTA rear window defrost
You need to move the plastic bushings/grommets to the new struts. The struts need to be electrically isolated from the body of the car. At least one of them does, the one carrying the +12 volts.
If the OEM bushings/grommets don't fit the new struts then they are not correct (junk).
RBob.
If the OEM bushings/grommets don't fit the new struts then they are not correct (junk).
RBob.
one carry + and other minus??
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Re: 1989 pontiac trans am GTA rear window defrost
On my '92 both sides are isolated. If not then there would be a different left side strut and right side strut, but there isn't.
Look at your stock OEM struts, that will tell you the same.
Have you tried moving the plastic bushings to the new struts?
RBob.
Look at your stock OEM struts, that will tell you the same.
Have you tried moving the plastic bushings to the new struts?
RBob.
#11
Re: 1989 pontiac trans am GTA rear window defrost
the top side is isolated, but problem is with bottom side ( witch attaches to car) the original bushing cant be taken out from old lifter, they are pressed in, i will destroy them if i will try to get out..
#12
Re: 1989 pontiac trans am GTA rear window defrost
When you have the new , improper lift cylinders in , presumably they are presenting a direct short to ground to the switched output of your defrost relay . This relay , like all the other electrical devices in your car , is supposed to be protected by either a fuse , or fusible link , and quite obviously whatever that protection is must have been bypassed because with the direct short to ground you haven't mentioned either blowing fuses or frying fusible links . So , please describe exactly what you mean by
"I put in the new lifters and when I push the button it goes to short cut"
Because if this "short cut" means the car's electrical power stops , and comes back when you release the button , and you aren't replacing fuses/fusible links , then like I said above you've got bigger electrical fish to fry before the frying ends up being your car's wiring harness or , perhaps , even your car itself .......
#13
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Re: 1989 pontiac trans am GTA rear window defrost
There's a schematic contained within this thread:
https://www.thirdgen.org/forums/elec...ch-shocks.html
Hopefully, it will apply to the OP's car and be of some help.
Don't over tighten the lift support-to-hatch bolts (see attachment here). 40-60 in-lb (= 3.3 - 5.0 ft-lb) isn't much torque.
https://www.thirdgen.org/forums/elec...ch-shocks.html
Hopefully, it will apply to the OP's car and be of some help.
Don't over tighten the lift support-to-hatch bolts (see attachment here). 40-60 in-lb (= 3.3 - 5.0 ft-lb) isn't much torque.
Last edited by paulo57509; 12-15-2017 at 03:03 AM.
#14
Re: 1989 pontiac trans am GTA rear window defrost
hehey,
yes thats strange that when i push the button the fuse dosnt blow up, but all cars electricity stops, when i release button all is oki. but that i can look in later and see if there is fuse in the line.
the problem is that iam in europe and i ordered lifts from usa, so i need to think if i need to send lifts back or i can think how to make
them isolated from car so i can use them. Because if i put in old lifts than all works and there is no problem with car.
but there is some issue with electricity i know that, because when i push button for rear trunk lock to open the brake lamp in panel also switches on. ( or thats normal )
yes thats strange that when i push the button the fuse dosnt blow up, but all cars electricity stops, when i release button all is oki. but that i can look in later and see if there is fuse in the line.
the problem is that iam in europe and i ordered lifts from usa, so i need to think if i need to send lifts back or i can think how to make
them isolated from car so i can use them. Because if i put in old lifts than all works and there is no problem with car.
but there is some issue with electricity i know that, because when i push button for rear trunk lock to open the brake lamp in panel also switches on. ( or thats normal )
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Re: 1989 pontiac trans am GTA rear window defrost
That circuit has a self resetting breaker, so when the short is removed, it closes the circuit again. So when you shut the car off, the ignition power for the latching side of the defrost relay is removed, removing the short. This circuit breaker is one of the two metal cans in the fuse panel, the other is for the power windows.
#16
Re: 1989 pontiac trans am GTA rear window defrost
i have these lifters in trunk, did any one also had problems with them? or iam just lucky
one more thing if any one know whats could be this plastic holder in rear between two seats:
one more thing if any one know whats could be this plastic holder in rear between two seats: