cluster n taillights

[ochn77]

anyone here know why my cluster and taillights would not be working right? it'll blow a 15amp fuse as soon as i turn on the lights, and a 20, and a 30amp starts to set fire to the car. the lighting switch tested fine. the relays tested fine. the lighting switch harness was smoking with the 30 amp. and the harness to the back was gettin hot.

i know the cluster backing lights are on the same fuse circuit at the taillights.

what would cause this?

someone said it's a short, but i've had a short before and the lights just didn't come on.

any chance it's a ground?

and the other thing... the cluster's reading wrong.. the RPMs are a 1000 low. and the fuel gauge is reading over full. and it's empty.

any chance these problems are stemming from a bad cluster?

[Jaysus!]

Paranormal Activity. Watch out.

[90LSCoupe]

pull out your cluster and try re-soldering all the joints.worked for mine.

[awelliott]

Seems like something is shorting to ground, and I wouldn't initially suspect the cluster. Try disconnecting the cluster and seeing if your tails work without blowing a fuse. I've driven short distances without a cluster and the tails work fine without it, so it should help you verify whether the cluster is the culprit.

[pnoye2]

Originally Posted by awelliott

Seems like something is shorting to ground, and I wouldn't initially suspect the cluster. Try disconnecting the cluster and seeing if your tails work without blowing a fuse. I've driven short distances without a cluster and the tails work fine without it, so it should help you verify whether the cluster is the culprit.

^ +1 ...although both tail lights feed from the light combo switch, unless your car is equipped with DRL, then source would be coming from that module.

Question Dave - were you, by any chance adding some "switched" accessories?


On the other issue...
- rpm false tach reading; how did you determine that <= just curious here
- fuel/temp gauge; fuel needle pegged to FULL <= faulty fuel sending unit could be the culprit

[ochn77]

i found which wires were getting hot. then i looked over that circuit's diagram. the red/black going to the tails was the same color as the one getting hot at the switch. so i cut the wire at the switch and routed a wire to the back tail harness connectors. the tails work fine with the switch now. but the cluster was still giving false readings. i tested the fuel gauge sending unit connecter as showed in the FSM. it wasn't giving batt volt.; it was giving 7.95 every time. **just remember though i totally forgot to test what the actual batt voltage was**

i know the RPM gauge was reading 1000rpm under because my coldstart idles at around 2000, and it was reading 1000rpms. also when the car's off, it's reading below the 0rpm mark by like a half inch or so.

the next thing i tried after testing the fuel gauge sender ***i have my dash pulled*** was putting things back on the connectors to see if maybe something is just on the same circuit and throwing the readings off. everything was cool until i plugged in a 2pin connector that's on the passenger side close up to the winshield. as soon as i plugged it in, it blew the 'doorlocks,trunk opener' fuse.

at first i was thinking that this would mean that the short is in the back, since two different things were not working in the back of the car on the same harness. **not forgetting the door locks and the cluster lights are on a front harness**. well, my ABS computer in the back has never really had the screws for it to ground properly, but it's always been that way. so i unplugged it. still blew another fuse. put it back to the way it was; put it back and grounded it. no help.

pulled the drivers fender off to see if the main harness coming from the underhood fuseblock was grounding out on the chassis.. no rub, no wear, no cuts.

i have a blown headlight bulb on the brights. i couldn't see that being the cause though because it'd still complete the circuit with the blown buld in place.

now as for the cluster. i did take it apart because i was already having problems with the cluster backing lights. couldn't see the rpms or the speed at night with the headlights on. all the bulbs in the cluster are good except the 'systemcheck' bulb. i'm pretty sure the system check light has never come on. and someone had already been in the cluster to put electrical tape over a flashing S3 light.

only place else i could think of was a: where the batter was rubbing against the harness, there's some ground wires there, but no wires rubbed down. or b: because the wire that was replace is the same circuit and color wire *red/black* that goes to a connector linked to the starter. it has the blck/wht wire going to the starter and the two grey's that go to the trans. the red/black had continuity from the cut wire opposite of the lighting switch*unused wire going into the harnesses* to the starter/trans connector's red/black wire. ....pulled the starter.. it passes, no shorts, just weak.. check the grey wires going to the trans. no wear. nothing that i can see that would ground out.

i'm at a loss here.

all i can think of to do is to now go through the doorlock/trunkopener circuit and re wire that one if need be and then see if yet another fuse blows on another circuit.

guy at orielly's said that you can test each wire by clipping onto it then onto ground and see when a fuse blows?? anyone else know how to do this type of testing? i know you can just continuity test cuz it'll still read it going through even if it's shorting.

[pnoye2]

WOW Dave, you really got some missed up wiring(s) to deal with here... electrical troubleshooting is no joke, but it seems like you're in the right path!

Got a few more questions and suggestions for you...
- check dimmer switch; for illumination
- does the engine/tach rpm correlates
- try swapping the light combo switch (plenty at the jy)
- replace ALL tail light bulbs

[ochn77]

u thnk a bulb cud do it even if thy wrk? ones blown. n system chk bulb on clustr. but i fnd why 2nd fuse was snappn. was pluggn wrng connctor. forgot the glove box whn pluggn stuff in. so the fuses arnt snappn now but still hav no clustr lights even tho the tails r on a seperate wire now. any chance ths cud b from usin a high amp fuse as killswitch on the ignition? wnt know for sure til i put the dash together. ill chck the dimmer. there is two switch tests for the dimmr n somthin else. relay under seat for dimmr. but i skippd tht to do wire.

[ochn77]

any more ideas on what's up with the cluster?

probably just have to find the short huh? well.. i tried resoldering, now i don't have coolant temp. the coolant's reading 'H', the fuel's reading 'F', and the rpm's still off.

still no cluster lights.

any chance it could be the 75amp fuserelay i'm using for a kill switch? even though the short probs happened a good month after putting it on?