67.5 Roadster Wiring Issue

[nissangirl74]

I found a lot of general info about my question but I want to ask a couple of specifics. Please don't flame me if the answer is here and i didn't find it.

Greg and I took the roadster out for a drive the other night. She fired right up but the lights wouldn't come on. He got underneath the hood and 'jiggled' the wiring harness and the lights came on. We drove to the store, no issues. When we came out of the store (only in there a couple of minutes) the car wouldn't start. The battery was completely dead. Some one jumped us off and we were back on our way. About two miles from the house, we went over the railroad tracks and the lights went out again. Luckily it was a deserted road and there was a full moon. We got her home but the lights have not worked since.

I started taking her apart Saturday afternoon. Everything was nasty, as most 40 year old cars are, so I cleaned everything I could get to. I removed the horn relay (since it was right there), cleaned it up and the connections and did the same with the headlight relay. None of the wires looked burned or damaged but I traced everything, replaced the tape at the connections and used new heat shrink to clean things up. I had one blown fuse that I replaced and checked all the others. I checked all the wires that run along the side of the car and there were no breaks in them. The protective tape that covered them was filthy, but there were no tears. The wires going into the firewall look to be well covered / protected also. I took some of that wrap off just to see what it looked like underneath and it looks like it did the day it came out of the factory. We have a wiring diagram of the car and nothing seems to be crossed. Also, the lights WERE working and i didn't just rip everything apart and play guess work about where things were supposed to reconnect. I redid one wire at a time.

We charged the battery, hooked it up and hit the switch. The horn now works (which Greg says it never did before) but I still do not have any lights at all. No headlights, fog lights, tail lights, brake lights, nothing. I'll be the first to admit that wiring is NOT my strong point so I am just looking for a starting point as far as the most common points of failure. My first thought was "Is the relay itself bad" and if so, how do I test it?

As a side note, there is no arcing or sparking at all, so I don't think it's a failed ground, but then again, I am no expert. I've tried to take ownership of this part because Greg hates wiring even worse than me, but I also need to learn what I am doing so when I go to wire up my S30, I'll know what I need to do. Any ideas would be helpful. Thanks!

[USsil80]

do you have a link to a schematic.... did you check to see if there where any fuses or relays that are blown or all corroded out...

[numbnuts240]

beck, what exactly did greg jiggle to get them to turn on? your problem might be a loose connection there. maybe corrosion on a pin or something really simple.

[nissangirl74]

do you have a link to a schematic.... did you check to see if there where any fuses or relays that are blown or all corroded out...

Yeah, I traced it under the hood as far as i could see (Couldn't do a lot of bending or getting under the car, just had surgery). Checked all the fuses, they are good. I'm just wondering if the headlight relay that mounts to the side of the car )is faulty. There are a lot of connections going to it, but the wiring for the horn relay runs through it too, and it works fine. There wasn't any corrosion, just a lot of dirt which i cleaned up with a wire brush and clean cloths. Everything is in amazingly good shape except for dirt and grime.

beck, what exactly did greg jiggle to get them to turn on? your problem might be a loose connection there. maybe corrosion on a pin or something really simple.

I have some pics, let me post them up....brb

[nissangirl74]

This is the part i think might be bad. All the wiring for all the lights goes to this relay.

The wires come out of this bundle, which looks sound, just dirty. I even unwrapped a lot of it just to have a look and there are no tears that i could see.



The wires for the horn also come out of this bundle and it works fine.



Here are some other pics, don't know if they will be of any use. Some of the wires are more difficult to get to because the cylinders for the brakes / clutch are right on top of them.

(the wiring i unwrapped, just to see what it looks like) (second fuse from the left was blown, i replaced it) (wires coming off the fuse box, leading to a relay which was very clean and not damaged) (I removed the old tape, cleaned the connections, applied new heat shrink wrap)

Like i said, i did one wire at a time so I am pretty sure nothing is crossed. I just don't know what i am doing wrong.

[USsil80]

did you check the connections before you wrapped them up to see if they are still good... you might even have a break inside of the wiring shield it self... but usally it is something stupid that takes forever to find... if you jiggled it and it worked i would start looking for a bad connection somewhere in that system

[nissangirl74]

I triple checked everything before i put it back together. I went to AutoZone tonight to see if i could find a new relay but of course they didn't have it. I'd like to find one and try that before I completely disassemble the wiring harness.

By the way, after we hit the railroad track the other night and the lights went out, they never came back on again, even though we tried manipulating the wires to make a connection.

Greg also told me that the wiring on this car has given him troubles before this so he's not really surprised.

Lovely....guess I know how my spare time will be spent....

[USsil80]

may i suggest a call to PAINLESS for a harness??

[AZhitman]

Nah, that'd be too easy.

We'll rewire the car in its entirety when it gets a full restoration.

For now, I just need the lights to work so we can drive the damn thing!

[NSR_s30]

Did just the headlights go out?...This might be silly but maybe the headlights burnt out?.....

[nissangirl74]

Did just the headlights go out?...This might be silly but maybe the headlights burnt out?.....

I still do not have any lights at all. No headlights, fog lights, tail lights, brake lights, nothing.

Greg has an extra relay that he knows is good so we are going to hook it up this weekend and see if that works. Keep your fingers crossed; for once, it would be nice if the problem was simple to fix.

[NSR_s30]

Ah gotcha, I skipped that part apparently. Hope the relay does the trick. I got my fingers crossed.

[nissangirl74]

The relay was OK. Turns out, the fuse going to that relay didn't have enough amps. Changed from 20 to 30 amps. Lights work great. However, when I bolted the relay back up to the car, the fuse blew. There weren't any bare wires showing but for some reason when the back of that relay touches the car, it blows the fuse. To fix it, I put two rubber stoppers between the relay and the car to keep it from touching. I threaded the screws through the stoppers, the relay is securely anchored, and the lights work perfect.

may i suggest a call to PAINLESS for a harness??

^^ has been avoided....for now

[USsil80]

so technically the relay is bad because it is grounding out through the case .... still though those problems are a total wrench thrower.. grats