Wiring for rear defrost, hazzard and "on-off" switch

supra_rulz

Member
Apr 26, 2010
111
0
16
Seattle, WA
first question is i have a '89 with a 1j swap

i took apart the dash few days ago just to see whats behind and noticed that there are no wires going to the rear defrost button. is there a "easy" way to fix that? i looked but didnt see any connector that looked like it was supposed to fit. would this have to go through a set of stuff or can i just connect......a 12v and be good?

hazzards
the plug for that is connected, but the thing doesnt work. i'm going to try and use a different switch but if that doesnt work, what could be the problem? i'm not sure why its not working because i guess it has to be connected for the turn signals to work....and they do, just not the 4-way....

"on-off"
how do you wire something so that it turns on and off with the key without tapping into any other pre-exsisting wires (such as the radio power that its using now)
 

RazoE

Boobs/Boost, my favorite
Jun 13, 2006
4,946
3
38
38
Los Angeles
www.cafepress.com
there should be a connector for the rear defroster, if it's missing, then someone certainly chopped the wires. Go to the junkyard, find a MKIII (wiring should the same), and cut that harness and try to splice it in...

as for the hazard switch, check your horn/haz fuse in the engine bay...

and finally, if you don't mind not having a cigarette lighter, you can use that harness, as it's a simple 12v switched source, and a ground, very easy to wire...
 

supra_rulz

Member
Apr 26, 2010
111
0
16
Seattle, WA
i looked a bit, i'll go look more, but i'm pretty sure its not there. so i'm going to have to splice it? the guy who owned it before me tapped everything to make it look nice. which group of wires would i have to start looking for?

oh, my horn fuse keeps blowing. i have no idea why either.....is there something in particular i should be looking for?

ok. IF (for whatever reason like a cop radar) i wanted to keep the cig lighter is there anything else i could jack? or do i have to wire something?
 

GrimJack

Administrator
Dec 31, 1969
12,377
3
38
56
Richmond, BC, Canada
idriders.com
You can keep the cig lighter... you don't use it instead, you use it as well.

Just use it for power and keep it plugged in. As long as you're not running crazy power off it - I'm running an electronic boost gauge, wideband, EGT gauge, temp gauge, and oil pressure gauge as well as the original cig lighter for my GPS, phone, or flashlight, depending on what I'm currently using.
 

supra_rulz

Member
Apr 26, 2010
111
0
16
Seattle, WA
GrimJack;1630513 said:
You can keep the cig lighter... you don't use it instead, you use it as well.

Just use it for power and keep it plugged in. As long as you're not running crazy power off it - I'm running an electronic boost gauge, wideband, EGT gauge, temp gauge, and oil pressure gauge as well as the original cig lighter for my GPS, phone, or flashlight, depending on what I'm currently using.

ohhhh, ok. well...i'm not 100% of the wiring but i think i'd be running just the power for a switch. not what the switch turns on. so i think i'll be ok. all my other gauges are wired somewhere else. lol

RazoE;1630577 said:
^--true true, I just don't trust it, seen too any cars burn..:D

I have my boost gauge wired to my cigarette lighter, and that's all I dare, haha!

dang that sucks.
but yeah, dont have a boost gauge yet. saving my money for one.

forgot to check the wire for the rear defrost. i'll do that tomorrow i guess :eek3:
 

supra_rulz

Member
Apr 26, 2010
111
0
16
Seattle, WA
ok, so there were no, zero, nada wires on the left side of the steering column. does the defrost have to go through something? or can i just hook up a 12v or something?