Shigen

Was driving in snow at normal speeds when the battery light came up on the dash. Moments after that the ABS,TRAC light came on and the radio started cycling on and off. I started to pull over.
When I parked, the dash lights, and needles went out, and the car started revving up and down off idle. I shut the car off at this point. It smelled as if something was burning. All lights are dim and there are no taillights. ANY insight on this will be GREATLY appreciated.

Shigen

Its a 94 LS (sorry forgot to mention the year lol)

Shigen

I believe it may be the alternator. Just from the way everything started failing ( radio, dash lights, engine power etc..) It is snowing really hard and I have no lower plastic guard underneath. Im going to clean any snow in there and let it dry completely, but I think it may be time for an alternator.

LScowboyLS

I think your suspicion about the alternator is likely, low voltage makes LS400 crazy!

i recommend you get a brand NEW battery, clean the terminals, and possibly even replace the end piece on the + terminal with the dealership part (they like to corrode inside hidden by the bolt)

then charge battery, install and check voltage with car off, should be 12.6V or higher

then check battery with car running at idle, should be 13.5V or higher, if it is not, then check circuit breakers, fuses, relays, but an bad alternator is the most likely candidate, and leaking power steering fluid on to the alternator is the most likely reason it failed (especially if it is the original NipponDenso alternator and your car has less than 200K miles)

Shigen

Thanks for the comment. As for the alternator itself, it was replaced before I bought the car last year.
(I have receipts for all the maintenance) I recently replaced my power steering pump, and I was
protecting the alternator so the ATF didn't kill it. Somehow while doing that, the 130A fuse blew.
Anyway, replaced that, and had no issues until now.


Everything looks clean around the pump. No leaks. I'm suspecting that either the alternator is defective, or snow got inside it and made it fail. ( possible?)

I have a new battery, and the alternator is on the way. My + terminal has no corrosion, but
i will replace it as a precaution.

Thanks LScowboyLS for your help on this.

LScowboyLS

snow will not make a car fail, there are LS400's in use in places that would make Utah heavy snow look like a light dusting (like the western slopes of Japan's Hokkaido island)

while the alternator may well be the problem, you need to make sure the existing battery is charged and terminals clean/replaced, and then do those voltage tests above - replacing a relatively new alternator doesn't do any good if it's not the problem

I would be concerned with what made a 130A fuse blow, a bad alternator won't do that, but whatever did do it could kill the new alternator!

Shigen

Thanks for the advice. The car does have the problem with the lights dimming when the brakes
or other loads are used. I've read that this could be that trunk harness issue.

I'm not sure if this is related, but I plan on doing some diagnosis once I can find the electrical diagram. Have had some issues with the battery arcing when its started, with the terminals tight.
I will post what I learned after I diagnosed this issue.

YoshiMan

You said you put in a new alternator recently? Where is that one from? I had an alternator Fiasco with an 89 Landcruiser once that took a string of replacement "lifetime alternators" before i wised up and just got a Denso Reman unit, which solved the issue.

LScowboyLS

here, you can check within just a couple of minutes and see if you have the very common trunk harness issue that plays havoc with everything and you probably have it!

open trunk and look at the curved part of the driver's side trunk hinge, there will be wire bundle in it or beside it, carefully take this bundle apart/untape/unshroud it and look at the condition of the individual wires inside, it is likely that at least one of them (often the white one) will be broken - all broken or damaged wired must be repaired, and that will fix a ton or seemingly unrelated issues!

python

iTrader: (4)

check the harness in the trunk lid hinge on the drivers side

PureDrifter

iTrader: (10)

link for trunk harness fix:
http://www.lexls.com/tutorials/lighting/bulbout.html

Shigen

Thanks for all the help guys! CL is where its at!

As for the alternator issue, I've found that it was in fact faulty. (defective, poorly built, reman)
The alternator I bought is a reman, but it's a Denso unit so hopefully it will go more than a year lol.

"You said you put in a new alternator recently? Where is that one from?"
Autozone lol. I said screw it to the "lifetime warranty" and got a Denso.

Installed it with my new battery, and my Fluke tester was reading 14.6v. I guess that solves the
charging system issue for now. Also noticed the airbag light coming on when I finished, guess I better learn that wire trick to get it to turn off haha. One of my alternator wires had a short.
The B+ wire had a small tear, and was rubbing up against the bottom of the P/S pump. This probably caused the main 130A to blow up.


Thanks again LScowboyLS, I will post my findings along with some pics when I do the trunk
harness.

Thanks PureDrifter for the link to the walkthrough.