Hi all, new here. I got 04 G35 Coupe. Short story; i have a bad wire (melted in areas) that is connected from fuse box behind battery to the drivers side strip light on the side of headlights. I began running a new wire and i know that fuse is also connected with the side marker lights, as well as the tail lights and license plate lights? right? I began following the lead the melted wire goes to to tap it back into the wire coming from the passenger side headlight area (there happen to be 2 on that side that were connected to this one.) My question: Where does the tail light wire come from? What color is it? Where can i find it?

i dont see it anywhere and the only possible location i could think of is in the center back of engine bay behind the firewall where the entire bunch is hidden and unreachable? any thoughts?

Thanks in advance. Hoping someone can give me some information. I have searched the pdf manuals i found online but they dont provide much information on this, plus they are very hard to understand/ read for me because i'm dumb.

-Nick

 

First of all, there were no "strip lights" on the side of the 2004 headlamps so I'm guessing you have modified lights maybe with an added LED element? That might explain the loss of that wire - which should never happen in this day and age as it should have popped a fuse before melting (dangerous!). If they are LED strips they may be pulling too much power from that circuit which already runs parking lamps, side markers, and license plate lights.

With a quick look at the "LT" manual for your car, I think from the IPDM (box of fuses and relays behind the battery) the wires to the marker lamps, parking lights and rear of the car should all be "R/L" which is Red with a Blue stripe.

The service manuals are NOT easy to read but if you grab "LT" and "PG" for your car you can eventually trace the circuit. They're here:
http://www.nicoclub.com/FSM/G35/Coupe/2004/ (thanks as always to the NICO club)

Hope that helps

 

I was talking about that long bar of light in the headlight that uses the same bulb as the side markers use. Yes, I was stupid enough to bypass the fuse for a few seconds to heat up the faulty wire to see which one was the one that kept blowing the fuse (My mistake, bad idea). I took the headlights apart because they were previously damaged from water and dirt inside and out. Did full restore and I upgraded to strip light in that long bar while I was in there.

I did find the "LT" manual and all that info. I know the wire is red with blue stripe. My issue is I cant find where the red/blue wire from the tail lights, etc. that leads to the melted one so that I can resolder it onto the new one I ran. I found where the lead from the other side headlight connected to old melted wire and will transfer that lead over, but I cant locate the one from the tail lights.

If I decide to follow the lead from tail lights to see where it comes out to the engine bay, where should I expect it to pop up? so far, the ones I found from the rear don't have the Red/Blue wire in the bunch. Also, when I looked at the patch of cables right by tail lights, there were actually three Red/Blue wires there. If nobody can help, no big deal, my mess, i'll just continue taking apart the harness until I find it lol. (smh*)

-Nick

 

Yeah, a can of worms but you'll figure it out.

Grab that other manual "PG" which has all the wiring info. And here's a preview: the body harness from the rear lights travels up the driver's side floor and makes a connection (connector B41) behind the driver's kick panel (near the inside fuse box) to the passenger compartment harness (connector E123). That harness then enters the engine compartment through the firewall near the driver's feet.

The book doesn't show which direction the red/blue circuit goes at that point, either to the left headlamp or directly to pin 22 of the IPDM. But it shows that the entire circuit is the same color wire so you should be able to find it joining at one of the connectors.

Make sense? Either pin 22 of the IPDM (connector E7) has TWO red with blue stripe wires coming off it, or you will follow the one wire to headlamp #1, then across to headlamp #2, the find it continues towards the firewall and the rear of the car..

At the rear red/blue run to both tail lamps (parking lights) and to the two license plate lights so that may explain why you see 3 of them. But that is the circuit you are looking for.

 

Saw connector B41 on the manual. Youre a big help, thank you. All the time i have been looking into the harness, i didn't know there was a harness link going through the firewall by the drivers foot area (i cant see it in plain sight from engine bay). I'll look into it later this week again when i have time. Work has been keeping me busy.

My E7 connector on IPDM only has one Red/Blue cable, that's why i am having a hard time finding where the link is to the back tail light wire.

This probably doesn't matter, but i found it strange how drivers headlight had the side marker lead cable soldered to the bar light (I guess it's a drl?) on the headlights with one lead going up the harness. However, the passengers side has two seperate cables for each bulb that run up the harness just past the IPDM where they connected to the Red/Blue cable.

Maybe i'm not connecting the big picture with the manuals or something, but where does it say which connectors on the harness contain which colored wires? Or is that info not available?

 

Yeah, the wire colors are only indicated in the schematics in the LT book and not in the PG book so it's awkward to trace. But the connector numbers and terminals are indicated in the schematic so you basically need to have both books open to figure out what's gong on...

So the red/blue that goes to the firewall might actually come from the left headlight. Like the circuit may run from IPDM to the right headlamp and side marker, then across the front of the car to the left headlamp and then back towards the firewall and continuing to the rear. I can't tell that from the books but you should be able to physically follow it.

Again, 2004 definitely did not have any LEDs in the headlamp. If you have a "light strip" then it's a mod so that could explain any odd looking wiring, etc... DRL (for Canada) was an entire different system which involved running your bright halogens at 1/2 voltage... blah blah blah.

Keep digging.

 

This puts me in an awkward situation. I'm assuming there's too many plugs in the cabin to take them out with the rubber boot (judging by the manual)? I have no comfortable way to check the center section of the harness that i cant reach. Drivers side has brake drum in the way and the boot with harness wires that go to cabin, top has A/C and Brake hoses and two (i'm guessing) coolant hoses going through firewall into cabin just above the harness. I dont know which corner to lift out. I'm also wondering if the fusible link box can be taken apart so i can slide the harness out from one side? Any thoughts?

I've already taken out the cowl and the wiper blade system. Dont want to deal with disconnecting the AC or the brakes. Assessing my options right now.

I've also been wondering if those new LED high/low H4 bulbs with the heat sinks and fans would fit into the High & fog light bulb housing? I'm assuming even if they did, they would generate too much heat. I just want to get rid of the yellow color. I dont like it.

Originally the headlights were OEM/stock. The wiring was all proper and untampered it seemed too. The only difference was like i said; passengers "light strip" had its own red/blue wire leading almost all the way up to the IPDM.

 

Being a sedan guy ... I could not figure out what you were talking about with the "strip light" but now I get it. The coupe's "side marker" is built into the the edge of the headlamp assembly and has it's own small bulb which shares the circuit with the 2nd filament of the turn-signal / parking light bulb - which is also in the assembly but more towards the center of the car. Attached pic below - but you already know this...

That's why the wiring seems odd, there are two bulbs in the headlamp assembly which run from that same circuit.

I don't know (and don't want to know) how you cooked that wire but it's doubtful that it's unusable for the entire length of the circuit. Most likely you only need to replace that first bit.

After the IPDM this circuit powers a total of 8 bulbs - front left and right side-markers (you call strip lights), front left and right parking lights (turn signal bulbs, also in headlamp assembly), rear left and right side-markers (small bulbs in tail lamp assembly), and two small bulbs above your rear license plate. If you were to unplug ALL those bulbs you could simply test the red/blue wire with a meter to see if it's shorting to ground anywhere. If it is, start by breaking the path after the right headlight and test again, etc... Or start in the rear and work your way forward until you find a problem. But I suspect it's fine from the engine compartment back so you shouldn't need to tear the whole car apart.

good luck

 

Attached is what i call the "Strip Light", and i call the side marker the separate light that is on the bumper. On my car, the strip light is always on as a daytime running light with the 2nd filament of the turn signal bulb. The side markers are always on too (so three bulbs from same circuit actually), but i am going to change that to use them as turn signals.

Since you don't want to know how i burned that bit of wire, i wont tell you . But the shortest distance of wire with a closed circuit will be the segment of wire that will burn if there is indeed a short. That circuit had wire soldered to it to lead to the rear lights, as well as the light on the other side. i only replaced the shortest distance from the IPDM to the faulty headlight segment, but i had to re solder the other leads from the old wire onto the new one so the other side headlight worked and the tail lights as well.

After the IPDM this circuit powers as much as 10 bulbs on my car: pair of front side markers, front strip lights, front 2nd filament of turn signals(? don't remember), license plate lights, tail lights, and the bulbs in the tail lights that are on the very corners.

UPDATE: So i got the headlights all worked out and they work the way they should, will show picture later tonight if you'd like to show you what i did. However, the Red/Blue wire leading to the rear of the car still does not power on those lights. I probed around and power is coming through from both links i made to get that wire lead connected to the circuit. When probing around in the back though, none of the three Red/Blue wires i mentioned before had power supplied to them. I plugged the bulbs into a alternate power source to make sure all the bulbs are working (they all lit up, works.) I almost feel like infinity is changing up the wire colors in spots because the wires on the tail light side for that circuit are green/red as opposed to red/blue on the harness side after the plug. Not sure why power is not going through, but have an idea or two. Looks like i need to dig deeper under the dashboard and toe kick panels.

 

So today i got the wire connected to the tail lights. Everything on the outside works. The only thing left is to do the last one for the interior button lights, but i have no clue where i should tap into it from? One last headache and then i'm done with this project. Next up, the wheels. ;D

 

Nicely done, glad you got your corners lit. OK, 10 bulbs... Front side markers in the headlamp plus side markers in the fenders. I guess you're modding all this anyway because these lamps were not originally on all the time as DRL, even in Canada. And if that 2nd pic is your car it looks like you've switched the markers to LEDs.

All good.

What do you mean by "button lights"? Glove box, ashtray, clock, etc? In that LT service manual they call that "illumination" and the section starts on page 182.

 

Wiring is tough sometimes. So this melted wire was the main power wire for all the lights? That's a lot of melted wire. Usually its in a certain area and you can splice it out, to bad the fuse didn't just blow. I might have an issue like yours except mine is in the engine control harness, hopefully not.

 

Those pictures I found on the internet. Not my car, but mine looks almost the same. I will look into that illumination section again once I get some free time. Got new full time job now and school on evenings so been pretty busy.

Yeah, wiring is never easy when you have melts or breaks you have to search for. If you read this thread earlier, I describe why my fuse didn't "just blow"
What's the worst part is that Infiniti decided it's a good idea to put so many lights onto one fuse channel and not split it apart. Instead they decide to save a dollar or two here and there. *smh*