electrical problem

[j3pz]

i was installing an aftermarket cd player, and when i finished, it didnt work. i know the head unit works cause it worked in another car. my clock on the dash never worked untill i hooked up the head unit, and when i connect the ground, the clock shorts out. also my alarm doesnt work (dont know if its linked. all fuses are good as ive just replaced most and tested the others. i ripped apart the dash to look a splice, a cut, or something and only found what looked like what was once a tapped wire ( had tap wrapped around with a little solder). i pm'ed jetjock the other day and got no reply so far, so if anyone could point me in any direction, id appreciate it

 

[blackout_89t]

What year car is it in?
What wires did you use for constant/switched 12V/ground?

 

[j3pz]

87t. it has an installation harness, so it just clips to the car harness, and the ground is a connector that goes under a screw, comes right off of the head unit

 

[forcefedsupra]

resolder that tap and check for burned wires.

 

[j3pz]

thanks but theres wires were never disconnected, thing was soldered on to those wires, then removed... i found another sypmtom, with the ground hooked up, the dome lights dont work.

 

[j3pz]

bumpity

still need help please

 

[cuel]

I rarely use the stock radio harness for an aftermarket radio(most of the time someone else already hacked it up anyway). It isn't hard to run a new harness for the radio power and ground wires, and find the stock speaker wires in the connector. I'd even go so far as to run all new speaker wire as well. Especially if I'm putting in a quality radio and new speakers. The bigger gauge(10ga. or 12ga.) speaker wire will give better sound quality than the tiny stock wiring.

 

[j3pz]

well the stocker was in place when i got the car, took it out and finally decided to put a cd player in, so the stock harness looks ok. i have noticed some splicing around the car so im just looking for tips/suggestions.

right now i have the apart, took out the gauge cluster and have everything disconnected and the radio still wont turn on. im going to try to trace to wires back to the fuse box

 

[j3pz]

wires look fine all the way to the fuse box. fuses all work...

 

[Kckazdude]

It sounds like you are connecting ground wires to wires that are powered. Not suggesting that you did it just a theory that I have seen proven many times. Trace all wires you are using and confirm them to have power or ground appropiatley.

 

[j3pz]

i had this radio in another supra and worked perfectly. i took it out of the other supra, and put it in this one, and didnt work. i used an installation harness so basicly plug and play

 

[j3pz]

do the clock and radio circuits connect to a common computer? ive been looking at the pre89 tewd, and i feel like a guy going into victoria's secret. thanks for all the suggestions

 

[Kckazdude]

20A dome light fuse and J/B #3 are both common points to clock and radio. The 20A dome light circuit also supplies power to the thef deterent system. I would pay close attention to that circuit for any problems.

 

[j3pz]

you know i cant get my theft deterent system to even work so could this be the cause? hmm i need to find someone who knows more about it... time to put that search button to use...

 

[j3pz]

ok i checked the headunit at the battery by connecting the acc and power lines to the positive side and the ground to the negative and it came on. i then checked the voltage at the harness, with the key set to acc, i had voltage on the acc line but nothing on the power line. im trying to check the pre89 tewd but its loading slowly.

http://www.supra.co.nz/87tsrm/uktewd/8688TEWD.pdf

edit: ok i followed my power line to a connector under the dash, near the steering rack. does anyone know what this connector is?