Need to find 12V at Ign on to repower the cig lighter.

I dont know what happened but I lost power to the cig lighter which is the same circuit that powers the pcm of my ls1. I dont know if I kicked the wire driving or something shorted out (my chassis harness has been cut and mangled by the last owner so maybe it'll make some of the purist on this board feel better that I'm restoring the cars function through rebuilding the chassis harness even though it will be piston powered)

Anyway I would like to use the factory fuse block but I only have about an hour this whole week to work on it. With only an hour I wont have time to go through each wire and check which have power when so I was wondering if you guys knew any specifics or had some wiring diagrams so I could figure it out a little quicker

Its a 1989 GTU.

If I dont get any answers I'll prob just do it a little ghetto and get power straight from the main relay with an inline fuse.

 

you do know that the cig lighter has its own fuse under the dash right? from the FAQ:

https://www.rx7club.com/attachment.p...hmentid=219918

I don't know what's left of your factory chassis harness, but have you checked the S5 wiring diagrams available free online?

 

I understand, As said before the cig lighter was wired to to stock fuse but I must have kicked the connection or something. I am going to run a new power wire, just looking for tips on where to wire it to. The factory cig lighter fuse would be good but I dont have a lot of time stripping and testing tens of wires. thats why I'm looking for the wiring diagrams at the least

 

wiring diagrams found in the FAQ for FC sticky thread

 

Wire it to the ignition harness. I'm not as familiar with s5 wiring, but you should hook it to either the IG1 or IG2 wire, not accessory (which is blue I think). I'd have to look through it to see what color it is. You want the one that still flows power when cranking but is not constant.

 

I wired it with a fused link to the 12v wire that excites the main relay I know this wire has 12v at IGN ON but I didnt check to see if it still had power at START.

Now it has power at IGN ON but I'm not sure if it has power during cranking. Anyone know if this wire has 12v while cranking? I think it doesnt because now the pcm of my ls1 gets power at IGN On and it primes the fuel pump but while cranking I'm still not getting spark. (my ls1 pcm is wired to the cig lighter to get appropriate power, which explains the thread title)

Turns out the pcm need power at IGN ON and START not just IGN ON. Would really like to know what wire has 12v at these times and HOPEFULLY (keeping fingers crossed) it'll start again.

 

Looking at the FSM IGN1 wire is the one I want which has power at IGN ON and START but it doesnt say what color that wire is. I can check it with the multimeter but wanted to know if anyone knew the color of the IGN1 wire

 

Do you know what this is?

A sign you should quit smoking. I think your car is trying to tell you if anyone is going to kill you, it's her.

 

You know I was glad to see that most people on here have responded positivly thus far to my question.. I was just waiting for the idiot to pop up. I can tell rom your screen name what you think of piston motors.. I really dont give a **** though.. please stay out of my thread

Thanks to others for the help and I think I am just gonna run it off IGN1 wire

 

.http://www.cochran-racing.com/FSM/index.html

 

That will work.

I may be wrong here, but I think that was a lame joke that had nothing to do with pistons/rotors.

When the inevitable ******* shows up, you won't have to wonder their intent.

Just chill and enjoy the camaraderie.

BTW, what is your drivetrain setup going to be?

 

Here is the ignition harness wire colors. The ACC wire will not retain 12v during crank but the two ignition wires will.

 

Just making sure there are no changes between 87 and 89 cause thats for an 87 mine is an 89.

Thanks a ton btw that makes it idiot proof. Trust me I need all the help I can get.

 

Thanks, now looking back at it.. I can see how that might just be a joke. Hard to tell the tone of peoples post over the internet.

Again it should help that yes I'm putting an ls1/t56 in the car but I'm really restoring it. It was used as a rotary powered race car and the last owner molested the thing. The chassis harness was a rats nest when I got it and the pinch welds under the door were shot. I did the sheet metal to fix the pinch welds and I'm obviously sorting through the chassis harness to make this car somewhat whole again. Its still gonna be a race/weekend car but it'll be in much better condition now.


The drivetrain is an ls1/t56 with aluminum driveshaft and T2 rear end. Has full t2 conversion and its been stripped out. The engine has full true dual exhaust. Its my first swap and its been about 3 years in the making so the car has been with me through a couple phases of my life already, finally getting it running initially I realized theres still a lot more work left. But we're getting through it.

 

LOL sorry didn't look that you had an 89. But I don't think it had changed. The best thing I could say since I don't have access to the 89 right now because I am not at work is to look at the ignition harness and if all of the listed colors are there then they are most likely the same. I suppose I could check my haynes manual too.

 

Actually only one of the two ignition wires hold power while cranking (Black/White). Black/red (just like the Blue ACC wire) drops when cranking but is otherwise hot in only the ON position. Black/red controls things like the blower and climate control and rear defrost that frankly should not be on either in the ACC position or START position.

 

Why don't you do it right instead? Pick up power for the PCM at the factory harness in the drivers floorboard or in absolute worse case (and someone hacked out the harnesses) then run it too the fuse box and pick it up coming from the ignition switch wires and run new wires.

The PCM power should be to/on Ignition 1, but the cig lighter should be too Accessory (as it always was). You do not want to put a 10 to 15 amp load (such as if someone uses the cig lighter) on the same circuit as what is powering a engine controller. That is just asking for voltage and PCM driver issues.

This is why I think most LS and alternative engine swaps are hacked in. Here we have someone that originally wired a PCM controller into the cig lighter circuit. 90% of the "swaps" do this kind of hacked in, BS work.

 

'm working with a pretty rough chassis harness to begin with. I had to restrore a lot of circuits already so yes its hacked.. but the car really didnt even work by most peoples standards when I got it, and now its getting back to the point where most stuff works and as I get things situated further.. obviously I'll work more on the details but right now we're just getting the basics taken care of.

 

I attached a series five diagram. It clearly shows IG 2 isn't energized when the key is held to Start. Only IG 1 is. The color of the wire that feeds the buss with IG 1 is shown in the jpg I attached.

 

Just so we're clear here B/W(F) stands for Black with white stripe?

Correct?

I dont know what the (F) stands for at the end

BTW I know I could figure this out with some time and a multimeter. But I get off work tonight at 6pm then I'm driving an hour to the storage garage that the car is stored in that doesnt have heat or light and its supposed to be around 0 degrees tonight with windchill. So that should give you guys a better idea of why I want to get my **** straight before getting there so I can get in and out ASAP.

 

(F) means the Front harness in the car. The front harness runs from the headlights to the dash board (with stops all along both directions)

and just a few wire colors:
B = Black
W = White
Y= yellow
L = blue
V = violet (or purple)

 

I was kidding. I didn't mean anything by it. Chill. I figured you'd have a laugh at it.

Think what you will of me.

I'll respect your request.

 

yeah man as I posted earlier lookin back at your post I noticed you prob didnt meen any harm just hard to tell tone over the internet.

I just have my flame suit on so tight when I post on this board that I get jumpy cause any mention of the ls1/rx7 swap has started a flame fest in the past. Glad to see things are getting to the point where each side can jab fun at the other.

 

The ignition switch has several plugs. One plug has a pure black wire AND a black/white wire. The black/white wire feeds IG 1 buss in the fuse box. The pure black comes from the engine bay fuse box and feeds the ignition switch. It has power on it 24hrs a day.

Look at the Interior fuse box in the jpg. You see the black/white wire leaving the ignition switch and feeding the IG 1 buss. And you can see which color wire feeds the IG 2 and ACC.

http://www.cochran-racing.com/FSM/s4...NG_DIAGRAM.pdf

Second jpg shows some of the harness in the car. The BLUE is the Engine harness, the Red is the FRONT harness. The clear or black and white is the EM or emissions harness.