DuoWing Posted September 10, 2013 Share Posted September 10, 2013 Well I have a weird issue. Up until recently I've had no issues with my interior lights/parking lights. I've even done the parking/interior relay upgrade harness on my 280z from MSA. My headlights are the HID dapper kit so those are all relayed separately as well. Anyway just the other day I took out the clock to gut it for my autometer boost gauge. I also removed the glovebox in the process. I haven't even reassembled anything yet, but now when I go to turn on my parking lights/interior lights I immediately blow the fuse over by the battery that's inline on the relay upgrade kit. I started swapping different fuses in, then finally I had one left a 30amp. I threw that in there and for some reason my interior lights/parking lights were working fine. The fuse wasn't getting warm or anything. I flipped it on and off several times. The next day I came home from work and went to flip them on to see if they were still working and again the fuse immediately blew. Turn signals, brakes, headlights, the brake light in the speedo, and hazards all still work. Just not the parking/interior lighting. I'm not really sure what's the best way to start tracking this down. Any suggestions would be appreciated. Quote Link to comment Share on other sites More sharing options...
jhm Posted September 10, 2013 Share Posted September 10, 2013 Sounds like the problem might be in the clock wiring and/or the glovebox courtesy light. If I recall correctly, the clock has separate hot and ground leads; but the glovebox light might use a body ground (i.e. the ground is accomplished through the light's metal chassis to the car's chassis.) Have you isolated and inspected those leads to ensure they're not shorting somewhere? Also, have you worked on the multi-switch recently (i.e. the main light switch on the steering column)? That's a pretty complex component, and it's not uncommon to have shorts in there periodically. Good luck with it. Quote Link to comment Share on other sites More sharing options...
DuoWing Posted September 10, 2013 Author Share Posted September 10, 2013 I remember having taken apart the combo switch, but I don't think I actually took it apart to clean the contacts for the lighting circuit. I'll have to give that a try. I've completely unhooked the plug that came with the clock pod and was still having it blow the fuse. The fuse on the passenger side is not the one that's blowing. Since I did the relay upgrade it's the one that's inline with the line coming straight from the battery. I don't know if that wire coming from the switch that is now trigger the relay is what could still cause me to have a problem, but like I said I'll have to take it apart. I also pulled the glovebox light out in the thoughts maybe I pinched the wiring or caused some kind of issue while removing the glovebox. Unfortunately I need to now go buy more fuses. I was attempting to do what I found in another thread. I took the bulb holder and the two wires that I removed from the old clock pod and hooked them into the fuse spot that keeps blowing. Flipped on the switch and tried working my way around the car to see if the bulb would dim or brighten, but I wasn't finding any change. I'll have to keep looking. Quote Link to comment Share on other sites More sharing options...
DuoWing Posted September 10, 2013 Author Share Posted September 10, 2013 Well I found the writeup on Z car about taking the light switch stalk apart, flipping the board and resoldering it. I did that and I'm noticing that the switch itself seems to be finicky. I don't know if that's enough to cause the relay to trip off/on can cause the fuse to blow? I would think the relay would be seeing a really random open/close for the main power wire and I suppose could short? Anyway when on the headlight position it seems to be fine, but when switching back from headlight to interior sometimes the parking/running lights will stay off. Sometimes when flipping the knob to just parking lights they won't come on until I play with it a little. Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted September 10, 2013 Share Posted September 10, 2013 Sounds like the Combo switch has some issue, but that doesn't discount any bad wiring. Likely it's one of the lights grounding to the frame. I'd pull loose the dapper kit and isolate that from the light system, then put in a 10A and see if it blows. If it does, then it's nothing with the dapper relays. next you can check that glove door light, since you remover it, it's likely a culpret, but maybe not. Did you rewire any of the running lights when you put in the Dapper? Finally, the clock wiring, It should go from constant power to ground, so likely that's not the issue. Quote Link to comment Share on other sites More sharing options...
Domzs Posted September 10, 2013 Share Posted September 10, 2013 Stop wasting your money on fuses . Find an old or new light socket ( with bulb ) with 2 wires on the backside or a test light . At your fuse holder ( the one that blows ) , connect one lead to one side and the other lead to the other side . If you have dead short , the light will light up . Start wiggling wires or unplug components until the light goes out . When it does , you have found your source . Good luck . Quote Link to comment Share on other sites More sharing options...
DuoWing Posted September 11, 2013 Author Share Posted September 11, 2013 (edited) Thanks for the tip Domzs. The only question I have on that is with the way it's setup. There's a wire going directly from the battery with a fuse inline. That wire then runs to the relay. The relay is tripped by the combo switch and then that wire from the battery passes through and becomes the new green/white wire for the parking/interior lights. Will the light ever actually go out as long as there is a bulb or two still plugged into their sockets? So far I got as far as having the bulb hooked up like you said and I took out all the sidemarker bulbs and one by one put them in noticing no change in the light at the fuse spot. Also I took the brake light bulbs out and noticed no difference. I'll keep going around unplugging. After following the wiring schematics I can see that there are several places where I can just disconnect large portions of the harness. So I can try doing that and then narrow it down. I'm thinking it's probably going to end up being under the dash in one of the gauge lights. Everything that doesn't work is entirely on the Green/White wire that feeds these lights. Even the double filament bulbs like the front turn signals and the rear brake lights still work on the single filament portion that is controlled by a secondary power. The green/white side controlling the other filament is the side that doesn't light. I also took my combo switch back apart and tried to see if I could tighten the box and everything up better. So I need to resolder the connections again, but hopefully the switch won't have the excess play that was allowing the connection for running lights to be finicky. With the switch on the second position or headlights, the headlights work fine and even the slight bit of rotating play that the switch had wasn't disconnecting the headlights or the running lights. I've also purchased another switch via ebay to test as well. Maybe I should start accumulating these as well until I can make the perfect combo switch. Thankfully since my Z has essentially no interior it should make getting at everything fairly easy. Also since I figure I'm probably going to be pulling the speedo out I can finally try and make sure my speedometer cable is connected properly and see if I do need to replace the cog in the tranny side. Update: I unplugged the connector on the passenger side that leads to the entire rear tail/parking lights to eliminate at least that portion for the time being, I've removed the front turn signal bulbs and side markers, no clock connector, disconnected hazard switch, and anything else with a green/white wire running to it. All I have left is the cigarette lighter, volt/fuel gauge, oil/water gauge, tach, and speedo to pull out. The bulb still lights up. I also took my switch back apart and made sure everything was tighter, re-soldered the wires and now it doesn't seem to have the finicky middle setting. The little wiggle on the parking lights step doesn't cause the connection to break. So one thing down. Also I know this car must have had problems in the past with the interior lighting as the connector coming from the combo stalk is burnt/slightly melted right around the pin for the Green/White wire. Edited September 11, 2013 by DuoWing Quote Link to comment Share on other sites More sharing options...
Domzs Posted September 12, 2013 Share Posted September 12, 2013 Yes . Like you said , one side is to bat. positive and if the other side is shorted to ground then the light bulb will light . Remember , the light bulb needs pos and neg for it to work . Quote Link to comment Share on other sites More sharing options...
DuoWing Posted September 13, 2013 Author Share Posted September 13, 2013 Well I've disconnected every bulb, even pulled my dash cover off so I could remove the Speedo and Tach and finally the light went out, but there doesn't appear to be any short. Although I'm glad I did this as the back of the Tach is a bit rusty for where the turn signal bulbs ground so I can clean those up a bit. Anyway driving me nuts thinking about it and I started thinking about what would have changed with removing the glove box. I've come to a pretty concrete thought. The glove box light. No problems until I removed the glove box. My glove box never had a light in it, so I never really knew what that switch was for. Then it occurred to me that the whole body of it is metal. After removing the glove box it would have just been hanging there. So all I would have to do is turn the switch for the lights on and it just needs to swing into the metal support for the dash and ground out. This would also probably explain why it kept blowing fuses until I started messing around to test fit my boost gauge and magically the lights were working again. Then after pulling it back out and coming back the next day the lights immediately blew the fuse. I did just to confirm my paranoia use my multimeter in continuity mode and put one end into the wire that feeds the glove box light and then just touched on various parts of the body and was finding continuity. So after I finish playing around with the dash I think I'll put everything back and see if I randomly blow a fuse again. I'm really hoping that this is the issue. Quote Link to comment Share on other sites More sharing options...
jhm Posted September 13, 2013 Share Posted September 13, 2013 The glovebox light....dang it, why didn't I think of that?? Quote Link to comment Share on other sites More sharing options...
DuoWing Posted September 13, 2013 Author Share Posted September 13, 2013 You know jhm I read your post a couple times, and then after you just posted I went back and re-read it. For some reason it didn't click until now. I swear you must have edited that in just a bit ago So much for my comprehensive reading... Quote Link to comment Share on other sites More sharing options...
Domzs Posted September 13, 2013 Share Posted September 13, 2013 At least the problem is solved and didn't have to replace too many fuses . Quote Link to comment Share on other sites More sharing options...
jhm Posted September 14, 2013 Share Posted September 14, 2013 Yep....always feels good to solve a problem that's been frustrating you for a while. Electrical gremlins can be a pain in the *ss! Quote Link to comment Share on other sites More sharing options...
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