electrical system FUBAR

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neurovish
Posts: 153
Joined: Tue Jul 30, 2002 9:24 am

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Car is an s14. Right now, it is mostly dead...I say mostly, because all of the electrical stuff seems to work except for what I need to work. The battery is new. I can turn on parking lights, emergency flashers, and brake lights, but not headlights. I checked the fuses and they're all good, none are missing. Other stuff that works: door locks, radio will accept cds and eject cds, dome light, clock.

The stuff that doesn't work: power windows, acc power, ignition, and headlights. (don't even get the click of a relay when I turn key to acc)

What happened:I was having problems earlier with my headlights, if my rpms were not high enough (approx. over 3k), the car would stutter if I hit my brights and a warning light would flash (I can't say which one...it was only very brief, I'm thinking engine but not sure). I pulled into a gas station to fill up, I tried starting the car and it wouldn't start...sounded like the starter wasn't turning over quick enough. On my second attempt it started without any problems. On the way home, I tried turning on my brights at a stoplight and this ended up shutting off the car, it started fine. A couple miles down the road I turned on my signal for a lane change and the car shut off completely (I thought I had the revs high enough to not trigger the car stuttering when I turned on the brights...hadn't had any problems connected to the turn signals). I managed to coast into a parking lot and got the car towed back to my apartment. Prior to the car shutting of, the battery light did not come on, and after it shut off none of the warning lights will come on.

Anybody had this kind of problem before?I have no idea what it could be, everything seems to be in order.


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C-Kwik
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Joined: Thu Aug 01, 2002 9:28 pm
Car: 2013 Chevy Volt, 1991 Honda CRX DX

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Electrical Gremlins can be the most difficult to find. The first thing you need to do is narrow down where the problem might be. This will require time, patience and a lot of trial and error. A friend helping you may be an added convenience. The first thing I would do is remove all fuses, fusible links and relays, except for those that are essential just to get the car started and keep the motor running. If the car does not start or run at this point, you can narrow it down to something within these systems. If it does start, check all your accessories at this point. If something comes on that should not, you have now isolated where the problem might be. If not, add a fuse and do it all over again. Keep doing this until you find something that should not be happening. Chances are that's a good place to start looking.

From what you are describing, there may be a short somewhere. Keep in mind a lot of relays have safety features now that just shuts down the relay in case of a short, so a fuse may never blow. You're doesn't sound like a simple short. It's either a multiple short, or a short between two unrelated systems. Perhaps in an area where the two systems are close together. Steering Column or in the fuse box.

fuzion
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Joined: Wed Jul 24, 2002 6:35 pm
Car: Cars.. Web/graphic design.. Yuppp

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id say check the alternator (thats what it sounds like.. when the one on my car was going dead big power surges killed the engine), clean the battery posts & cables..

Check for corrision.. check for split/heated main wires n stuff

I bought my car used, I was driving it and the ebrake light came on and the entire car stopped.. I figured I was screwed and the car was dead, turns out, previous owner took out the car alarm and it was hooked to the ignition switch wires, I took the entire interior out (dash, everything) and spent all night trying to find the problem, next morning i go out and look and there is an ignition wired burned in half because the prev. owner twisted it together with electrical tape..

Dumb asses :)

Anywho.. Hopefully one of these things will fix your problem, if not I hope you find out whats wrong with it!

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neurovish
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Joined: Tue Jul 30, 2002 9:24 am

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battery is brand new, the one that was in the car at the time was really old and crusty...seemed like it still had a strong charge though, but I replaced it anyways. The only signs of excess current I've found so far are on the red clip that's on the positive terminal of the battery, the driver's side of the plug (LHD car) is partially melted along with some insulation it looks like, the wire right next to it is fine...I don't know if this is something new or been that way for awhile. A quick continuity test between the positive terminal on the battery and part of the wire where the insulation is kinda burned off shows it's still good. I would like to test it further though, anybody know where specifically this wire leads? (in the fusebox someplace).

I tried taking out the sockets for the fuses from the box so I could get a good look underneath to see if anything is obviously gone and do some more continuity testing, but I could not get them out very far. I got them unclipped, but it felt like there was a wire holding down the passenger side bank...is there something I'm not seeing, or will a good tug do it (which I'm rather cautious of doing when working arond the wires...and yes I did make sure to take off the neg terminal of the battery and make sure it wasn't touching anywhere :) )....so, any hints with getting the sockets for the fuses out?

Another question....fusible links, I cannot find any, are they under the fuses such that you have to detach the fuse sockets? Are they the fuse like things that don't look like relays or common auto fuses in the fusebox?...I thought they looked kind of like spade connectors with weird insulation around where the wire goes into the socket.

Any answers would help a lot.As far as getting to the wires under the dash...man, I dunno...it's more confusing than the tangle under my desk...plus there's a pesky a/c tube hiding everything. I'm pretty close to just taking it to nissan...I'd feel really bad if I pay them $100 just to find that it was something semi obvious and easily resolved though.

....also doesn't look like this car had an alarm on it, but I could be wrong. I've spent more time upside down under the dash than I would like, and it doesn't look like anything aftermarket was installed...is there anything specific to look for?


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