Electrical Problem

[halxi]

Ok so last night i was driving around town and all of the sudden when i hit the brakes, my stereo shuts off, ALL electrical things shutoff (guages dropped to zero but the car still ran) and all lights, then my batt light came on. I left off the brake and everything powered back up again. Well i instantly drove home (in fear if it died it wouldnt start again) and shut it off and let it sit for 5-10 min. Then i went back out, turned the key, and it fired right up and its been acting normal all day today.

So my question, wtf could this be?

one person has said alternator, another has said the batt or batt ground, and my dad and i think it might be the inline fuse for my amp.

All help is appriciated.

EDIT: Btw, when my bass hits on a normal day when my car isnt acting weird, my lights dont even dim the slightest bit. But then it did that.

[89T]

did you run wires near the brake pedal?
if so explain?

[Vanilla Sky]

i would think a loose connection somewhere. make sure EVERYTHING is tight in the electrical system. be sure to check your main fuses in the engine bay (the ones that are covered up in the fuse panel), and check the contacts around them for corrosion.

[halxi]

did all that, everythings good.

It just randomly did it today (and it got me pulled over :pc: ) again, so im like.... uhhh wtf?

ill go over everything again tomorrow, tonight my project was re-do my rear suspension (finished) and put in my header, and run open header for awhile until i got my exhaust cut/welded up. Well... ONE bolt that holds the down pipe to the header was rusted to the flange... couldnt get it off, so i put it all back together (the stock stuff) and said fuck it for tonight... tomorrow im going to have it torched off.

[Vanilla Sky]

take your car in and have the electrical system load tested. i believe autozone does this for free.

also, under what conditions does your car do this under? music loud and you apply your brakes? is your battery new? alternator? how much of a load are you putting on your electrical? newly installed things (i know your audio is new, but anything else)?

how does your car run when this happens? does it bog down, miss, or rev up? have you had the engine shut off when this happens?

is your power line to your amp fused? if so, is the fuse properly sized?

do your brake lights work correctly when the car isn't doing this?

does this only happen when you're moving, or can you make this happen when you're parked?

i recommend checking everything out that i listed there and coming back with your results. this seems like an odd problem, but if you can replicate it and tell us exactly what made it happen and under what conditions, we could help you so much better.

[halxi]

thats just it, its COMPLETELY random.


how does your car run when this happens? does it bog down, miss, or rev up? have you had the engine shut off when this happens?
Car doesnt miss, bog down, rev, nothing when this happens. It died at idle tonight when i was rolling my windows up, but thats paritally because i need to adjust that valve (forgot exact name of it right now)


is your power line to your amp fused? if so, is the fuse properly sized?
Yes, fused off of a new battery, fuse is approx. 12" into the line. 20amp fuse i believe, going to try upgrading to eliminate the problem


do your brake lights work correctly when the car isn't doing this?
My brake lights work perfectly when the car is and is not doing this, my friend said they actually got brighter when the problem started tonight (he was following me in his lude)


does this only happen when you're moving, or can you make this happen when you're parked?
so far it has only started when i was moving, but continues when im parked. Hasnt actually started while being parked.


Ive been talking to vanilla on aim about this, but i thought it would be helpfull to post my answers in the thread for future reference.

[catalin]

Are your battery terminals on tight???? and if you wiggle the ignition or wirig under the steering going up to the ignition does it also turn power off??

[thabeana]

How ironic this is...I just recently had my car undergo the same symptoms yours did. When I'd press the brake, the lights would dim, the battery light would come on, etc. I was driving home on an 8 hour drive, and had 3 hours to go...car didn't make it those last 3 hours...lol The problem that I found was my alternator. The brakes are what made my amp light turn on, and shortly after my stereo too shut off, then my lights got dimmer and dimmer (digital clock went out too....lol) no more cruise, and it finally died as i came to a rolling stop. I don't know if you noticed that when you kept it above a certain RPM that the amp light would turn off? For a while it would stay off if I kept it above 3K rpms, then 3100, and it consistently had to keep going up in RPMs for the amp light to stay off. Hope this answers your question(s) or problems. If you have any more PM me I just went through this w/ mine! Again hope this helps:lol:

[halxi]

yea, stereo runs fine, now im having problems with my motor powering in/out

it will bog then just kick over, like MASSIVE vtec, and start pullin like it should... its really beginning to piss me off

[Vanilla Sky]

yeah, i'm thinking it's the voltage regulator going out. when that goes, you replace the entire alternator. chances are that thi would be picked up under a hard load test at any autozone.

[w261w261]

Also while you're at it, make sure you have a good ground strap from the battery.

[wyked.styles]

I have a similar problem only when the car is moving and when the steering wheel is turned left, hit a bump, downshift. or dump the clutch. Everything turns off however does not affect the performance of the car at all and my batt light does not come on. it is anoying as hell

[HondaBoy]

i had this problem, sorta. i'd hit the brakes and the lights would all dim, as if i'd turned on the parking lights. it was a long time ago, but i do remember it turned out to be a light bulb in the tail lights that was going bad, so bad ground i think was my problem.

[POS carb]

if the problem goes away and the car can still start then your alternator is fine.

I would think you have a short circuit or bad contact. If it happens only when yuo hit the brakes then thats where you should start checking, check the wires for the brake pedal switch, make sure they are not exposed. You should also check the battery connections as a sudden stop can shift the battery and also make the contact come loose.

Your other accessories should not shut off if the problem is isolated to your amp power cable unless there is a huge short circuit, in which case you can tell by removing the power cable and see if the problem goes away

[w261w261]

Does the problem occur when you hit the brakes each time? Or a bump, or something that would cause a shift in an already loose connection? Have you checked the battery after it happens to see how many volts are showing?
Maybe check it when it's running fine to see if its 13.8 or so?

[bobafett]

yeah i had this problem (the first time) my negative battery cable had come loose, and on the freeway it was getting intermitant contact with the post. when i press the brakes, or used turn signals, my radio would shut off (coming back on when I stopped pressing the brake pedal). i put the battery cable back on, and was fine for years.

the next time that happened, my alt had begun to kill my optima, and once i replaced the alt all was well (of course i have managed to kill like 6 optima batteries over the last 2-3 years, heheh)...

I want to say its a bad connection somewhere, or the alt.... just like others are saying. wouldnt be that hard to disconnect the amp for a while to see if it is causing your problems, but i don't have the gut feeling that the amp/stereo has any effect on your situation.