phillipin

Ok this is very very wierd

When i press the brake randomly the bad/broken bulb indicator light comes on but my brake lights are good. And half the time when i brake and that indicator light comes on the Reverse "R" light will come on and the car will down shift not so smoothly.

I talked to a very knowledgable car buddy he said it will probably have to do with the abs system since that the only real electronic connection to the ecu that would cause a downshift.

Also my car is starting weak, like the starter isnt getting enough power, i've sanded the terminals and connectors on the battery they feel slightly loose so i'll try tightening them.

Now as well a month after flushing my power steering fluid its running low, so its possible i'm leaking fluid again grr...

But any help for that wierd braking downshift problem, it was like once a week, now it every time i drive the car. It has no rythim to it, no pattern its completely random.


EDIT:

I dont think the PS is leaking to the alternator, i dont see any visible leakage and no smoke coming from the alternator while idleing for at least 5-10 minutes. probably sucking it into the vaccum line... or the rack is leaking but i have no visible spots where i park the car

I swear i love the car so much but these little issues keep coming up, makes me wanna patch the car up and trade it in considering i paid 4900 for it and can sell it for 6000 .....hrmm i dunno

Kansas

This is a very common problem on the early LS and is almost always caused by a broken wire (white with black stripe, I think) in the left hinge of the trunk. To fix, pop off the cover on the hinge covering the wire, unravel the electrical tape, find the broken/cracked wire, cut it at the break, splice in a bit of wire (1-2 inches) -- solder it or use wire connectors.

You can find posts about this problem by searching this or other Lexus LS400 forums for "hinge".

I thought my 90 LS was a goner when this happened in the summer of 2002. It was the first day that I used an on-line Lexus forum and I found the solution within a few minutes by searching.

Good luck! (and tell us if this fixes the problem.)

phillipin

Wow that was very very imformative, i was thinking of downing a shot of remy martin and just setting the car on fire at this point, just kidding of course I love my LS i just dont love the quirks.

I'm definitely going to be in the trunk tomarrow looking for the crack in the wire, Yeah it is the freakiest problem, you brake and lights go crazy tranny gos nuts, if its caused by a crack in a trunk wire thats a seriously wierd design flaw

although if its wiring in the bend of the hindge on the trunk this would make sense it would go out a month or so after i bought it, the car was never driven by the previous owner and i use the trunk everyday for my laptop bag and various stuff too much stress on the old wiring

dieseldust

This sounds almost impossible. However, I have the same problem of stepping on the brakes, "R" light goes on and tranny down shifts. Most annoying. It was suggested that it might be some sort of solenoid. I'd never have thought to look at wiring in the trunk. I'll be there in the morning.

PureDrifter

iTrader: (10)

90% chance its trunk hinge wiring harness having a frayed wire.

5-year edit: more detailed steps to fix: http://www.lexls.com/tutorials/lighting/bulbout.html

19psi

100% guarantee it's the wiring on the trunk hinge. same thing was wrong with mine when ibought it, (i got a very good price on it because they thought there was a serious problem) i drove it home, jumped in the trunk, found the broken wire in the harness, spliced it up and never had a problem since.
of course, being a mechanic at a lexus dealer, i saw the problem first occur in an old ES, so i had a good idea of where to look...

trukn1

I have a break in the wire on my trunk hinge as well. Can I use just any gauge wire, that is close, to splice and replace?

19psi

if you don't have the same size, use larger. don't use smaller. it's a very important(as we see from teh problems it causes) ground that carrries teh signal for many circuits. a smalle rwire will have too much resistance and may cause problems.

PureDrifter

iTrader: (10)

16-14awg should be alright.

id use a 12-14 to be safe.

pRaHjeC

you know, my car did this when i bought it, and i never looked for the wiring or anything. all i did was put in some new bulbs and it actually took care of everything. but my bulb out light still stays on. but for some reason the downshifting and the R light coming on when i step on the brakes stopped happening. i'm thinking maybe the old bulbs cause too much resistance in that circuit and it just needs new bulbs to let the amperage flow better. pretty weird.

Kansas

The wiring in your left trunk lid hinge may still need attention. The R light and shifting problem can come and go until these wires are fixed. It takes only a few minutes to inspect and fix the wires in the hinge.

pRaHjeC

yeah i'll take a look at it. thanks for the heads up!

black_LS

I'm having a pretty weird problem with my 95. My bulbs are fine but the bulb warning light comes on and off as it pleases. I know it's a second gen, so it might be different. Any ideas?

PureDrifter

iTrader: (10)

loose base connection u need to replace the harness most likely (for one of the particular bulbs)

chadrouse

If I had not found this thread I would have had to spend mega bucks I am sure at the local dealership. The wires in my trunk were broken as well. Fixed them and now no problems!!! Thank you all for posting.