jeremystephens

ok im at a loss here: 96 4 runner ltd.
the symptoms: charging light blinks twice then the abs light comes on and stays on if the cabin blower is on it kicks up. then this morning it happend and my headlights go dim then out so i flipped the brights on and they did the same. now the headlights dont work and the running lights as well.my third brake light was melted. i had the alternator bench tested and it passed three times. i bought a headlight relay but havent put it in yet. could it have blown all the bulbs on the headlight circuit.
i had led bulbs in the rear turns but i am going back to regular. why would my headlights and parking lights fizzle out. what the crap this thing is getting sold as soon as i fix this.
i have seen elsewhere that the 3rd brake light can cause weird things to go on.

ANY help is greatly appreciated guys

Jeremy

jeremystephens

oh yeah i checked all visible wiring and nothing is exposed or broken
i cleaned the terminals and wires to the battery the battery is <1 yr old
there is some corrosion going into the wire that goes into the relay/fuse box under the hood

97ltd4x4

Sounds like a fuse box/harness problem...If that wire is corroded it could well be your problem...Heavy wtite wire..It directly feeds your ALT 100A main which feeds heater relay,tail relay,15Adefog,10Astop,7.5A alt....

The white wire also feeds,60A abs,headlight relay,among other systems.

You really need to do voltage drop tests from your positive post and work your way through the white wire and through your fuse block anything over .1 volt I would get concerened......You could do a quick check with a test light and once you see it dimly lit or not at all,really inspect that area...

Oh,and if you have anything aftermarket alarm,radio,ect installed disconnect it for testing.

Good luck

jeremystephens

so you suggest starting at the battery with the white wire and test my way up it to the fuse box then test esch component within it seperately. this sounds good. The white wire is corroded around whrer the lug joins the copper. so much in fact that a pretty steady stream of white powder is fallinf out of it. i hope this gets it. i replaced my led turn bulbs with 7440's and replaced my 3rd brake bulb today. i also tried the new headlight relay to no avail it turns out the old one was good.

just 1 more question.
my headlights still arent working will loss of voltage due to the corrosion cause them to go dim and burn out because they still arent working at all as well as the running lights. the relay is engaging i can hear it. whats up with that

SoCalPaul

If your lights burnt out, most likely you have an over voltage situation. Lights don't normally fail due to low voltage. Was the alternator checked in the truck? I would suspect the voltage regulator.

Paul

mnmontana

im sure its not the issue, but figured id point out what I read about someone else having a somewhat similiar issue.

Check the harness that rests above the e-brake, its supposed to be about an inch above it, but see if it fell, as has since been rubbing through.

After that, I would suggest disconnecting the ecu and battery, and with a buddy and 10 feet of wire, trace down each wire and check for continuity where it shouldnt be... good luck, sounds like its gonna suck, lol.

98runner210

Don't trust the alternator tests too much either. I have seen several alternators that have intermittent problems...sticking regulators etc. Those tests they do may not show something that isn't malfunctioning all the time.

jeremystephens

ok is this harness above the ebrake handle in the center console or do you mean the ebrake itsself on the rear axle. also i thought it sounded like an intermittent alternator condition but i needed to hear that from someone b4 i dropped that dough. i will check the harness first if i dont find it im gettn a new alternator. its been bench tested but like you said it wont show an intermittant problem. thanks

jeremystephens

ok i checked the headlight and running light bulbs they are blown
they have zero continuity. also i hooked up tje volt meter to the batt and watched as i revved the engine heres what happened:

just after start up as i watched the abs and charging light come on the voltage jumped to 17.35 at idle. it also seemed to drop the idle a little too maybe 25-50 rpm. then as i revved it got up around 19.9 volts so i let it idle again then it wntt down to 14.4 volts as it did the idle seemed to bump back up by 25-50 rpm. the lights of course stayed on in the dash as expected so i let idle and come up to temp.

after reching operating temp i revved again for 5-8 mins and nothing happened so i revved again for 4 mins then the volts all of a sudden jumped up again to around 20. so it is much harder to replicate after the engine is warm.

heres what i think you tell me if im wrong:
1. overcharging caused the bulbs to burn out.
2. the alternater is going bad more specifically the regulator.
3. im gonna have to buy a new alternator and $40 worth of bulbs

if there could be anything else that would cause this

98runner210

i would start checking wires and fuses too makre sure nothing fried. odd that it surged so hard to blow bulbs but no fuses

jeremystephens

yeah i thought that too so i checked them all and they were all good so i checked the big fuse blocks and relays too but it didnt get anything just the headlight/running light bulbs

98runner210

well then again i have heard of low voltage not being good for bulbs too. I am not sure why. I used to have a Chevy that used the low beams for the DRL. They were not full power low beams though. I went through a set of headlights about every 6 months. The dealer and a few other places said it may be because they are running dimmed. Maybe high/low voltage fluctuations made them burn out.

PS. Good luck with your alternator. It seems now no matter where u buy or what brand u buy, you may have to go through a few of em before you will find a good one.

jeremystephens

thank you all for your help. i will keep you posted i will pick up the parts 2morrow so well see.

jeremystephens

alright im done the new alternator fixed it
thanks 4 the help