Reverse Light Coming On When Braking

[sisterpete]

today my reverse light in the dash, "R" started coming on when applying brake?

any ideas? if this has been covered, sorry for the repost... been a few very rough days physically and i feel kind of spaced out....

thanks

[1990LS400]

One or more broken wires in the left trunk hinge. Splice in new wires. It happened to my 1990 LS400 too. A very common problem on the early LS400.

[sisterpete]

thanks for the reply.... new question... possible same problem...

the other day, my trunk key stopped working won't turn, must be something inside...

now going out to check on this wire loom, my trunk will not open from the switch inside...

wife said it opened earlier for her... oh brother...

is there a way to get into the trunk and open it from the backseat area possibly???

and im guessing this switch problem may be the same wire look?

does that loom have the gas door included?

thanks

[1990LS400]

thanks for the reply.... new question... possible same problem...

the other day, my trunk key stopped working won't turn, must be something inside...

now going out to check on this wire loom, my trunk will not open from the switch inside...

wife said it opened earlier for her... oh brother...

is there a way to get into the trunk and open it from the backseat area possibly???

and im guessing this switch problem may be the same wire look?

does that loom have the gas door included?

thanks

The trunk key problem is a separate issue -- you might try lubing the lock cylinder with lube made for locks -- do not use WD40 or silicon spray. The trunk lock cylinders sometimes simply wear out.

There is no access to the trunk from the back seat. Don't know if the trunk lock switch is in wire loom at the trunk hinge -- might be. Don't know about the "gas door" circuit either -- probably not.

Unwrap and closely inspect the left trunk hinge wires. It is possible for wire cores to break without the insulation breaking so wiggle the wires to make sure that has not happend. The trunk hinge wires can require repairing over and over so keep on top of it.

[sisterpete]

thanks... guess my biggest problem is getting inside the trunk?????

[VBdenny]

When the "R" light comes on when you brake, it means the white wire in the pack in the left trunk hinge, is broken. Happens all the time on these. I read somewhere that Lexus made the wire too short but I suspect time and repeated flexing is the main issue. I spliced in a small section and fixed everything. Keep in mind that when that wire is broken, the shift pattern is severly compromised. As far as the trunk issue, that IS your biggest problem. Maybe more than one wire broke and the other one locks you out of the trunk so you are forced to go to a dealer. They wouldn't be that sly, would they?

[eatingupblacktop]

thanks... guess my biggest problem is getting inside the trunk?????

Before heading to the dealer, try a couple of things. After inserting the key, pull it back out a tiny bit then try turning. Try different increments to see if one works. You can also try pushing down on the trunk lid and turning the key. The latch might be jammed preventing the key from turning. Pushing down might free the latch. Last suggestion is to disconnect the batt, then try the key. Once you do get it open, I would fix any wires that need repair before closing the trunk again.

[sisterpete]

man thats the word for sure... get it open... FIX EVERYTHING ha ha

man knowing what color wire is really nice... THANKS for that info...

you said the following "Keep in mind that when that wire is broken, the shift pattern is severly compromised" which i am guessing might be the answer to the follow... i was actually able to drive the car tonight, and noticed when i do brake and the "R" lights up... immediately it downshifts... obviously the faster you are traveling, the more noticable it is... so i'm guessing i am on the right track.

ive tried a few of the tricks to get the trunk open... but not the battery yet. i noticed the key not working, but just had not had the time to look into it.. then this switch stopped working... thats what i get for not getting right on it...

thanks to all who replied... love this forum... have never failed to get good solid answers and fast...

wish i knew more so i could help others... maybe some day...

[VBdenny]

Communication is they key to learning. You say you wish you knew more but you have already taught others. My trunk has never had this problem but in the the event it does I sure would like to know what the problem is. We all learn from each other.

Regarding the shifting, I think the computer puts the car into some weird default pattern when this wire is open. My car did all kinds of strange shifts. I guess what worries me more than anything else is why a key won't open a trunk. Was there problems with the key or lock prior?

[cubaski]

When the "R" light comes on when you brake, it means the white wire in the pack in the left trunk hinge, is broken. Happens all the time on these. I read somewhere that Lexus made the wire too short but I suspect time and repeated flexing is the main issue. I spliced in a small section and fixed everything. Keep in mind that when that wire is broken, the shift pattern is severly compromised. As far as the trunk issue, that IS your biggest problem. Maybe more than one wire broke and the other one locks you out of the trunk so you are forced to go to a dealer. They wouldn't be that sly, would they?

When you refer to the white wire in the pack, are you refering to the wires inside the trunk hinge? I ask because my 1992 LS is doing the same thing when I apply the brake the reverse light comes on. I would gladly appreciate it if you could point me to right direction.

Thank you

[VBdenny]

If you send me an email address, I'll send you a Powerpoint I made of mine when I repaired it.

Denny

[1990LS400]

When you refer to the white wire in the pack, are you refering to the wires inside the trunk hinge? I ask because my 1992 LS is doing the same thing when I apply the brake the reverse light comes on. I would gladly appreciate it if you could point me to right direction.

Thank you

The wire harness is not "inside" the trunk hinge but are attached to the left trunk hinge and flex each time the trunk lid is opened and closed. Unwrap the insulating tape from the wires at the left trunk hinge and flex each wire to determine if wire cores are broken. The wire insulation may not be broken but the wire cores inside the insulation can be completely separated or barely making contact. Splice in new short lengths of wire -- soldering the connections are best but not absolutely necessary. The wires may break again in a few years and you may need to repeat the process.

[VBdenny]

Got that right. After two repairs, I configured the wires outside of the hinge so they didn't bend so much opening and closing the trunk. I spliced in a little extra on a couple that looked like they had been bent a lot. I taped it all up using a continious piece of tape unlike how the original was taped (which was challenging at best) and it has worked fine ever since. My suggestion is not to try and put it back in it's original location, leave the wires outside the hinge indent. You can't even see it when standing behind the car.

[cubaski]

Got that right. After two repairs, I configured the wires outside of the hinge so they didn't bend so much opening and closing the trunk. I spliced in a little extra on a couple that looked like they had been bent a lot. I taped it all up using a continious piece of tape unlike how the original was taped (which was challenging at best) and it has worked fine ever since. My suggestion is not to try and put it back in it's original location, leave the wires outside the hinge indent. You can't even see it when standing behind the car.

Thanks guys, I found it, repared it, and were back to normal. This is a wonderful website, I thank God for the person or persons responsable for creating it.

[cubaski]

When you refer to the white wire in the pack, are you refering to the wires inside the trunk hinge? I ask because my 1992 LS is doing the same thing when I apply the brake the reverse light comes on. I would gladly appreciate it if you could point me to right direction.

Thank you

The wire harness is not "inside" the trunk hinge but are attached to the left trunk hinge and flex each time the trunk lid is opened and closed. Unwrap the insulating tape from the wires at the left trunk hinge and flex each wire to determine if wire cores are broken. The wire insulation may not be broken but the wire cores inside the insulation can be completely separated or barely making contact. Splice in new short lengths of wire -- soldering the connections are best but not absolutely necessary. The wires may break again in a few years and you may need to repeat the process.

Jim,

I've been trying to resolve a power issue with the fog lights on my 92 ls400. I tested the light conducters and fouond no power, I then tested the fuse that's under in the cluster pannel and theres power but not circulating through to the lights. Is there a breaker or a wire that this particular model suffers from being replaced or something? I appreciate it if you can point me to the right direction.

Thank you

Cubaski

[1990LS400]

Jim,

I've been trying to resolve a power issue with the fog lights on my 92 ls400. I tested the light conducters and fouond no power, I then tested the fuse that's under in the cluster pannel and theres power but not circulating through to the lights. Is there a breaker or a wire that this particular model suffers from being replaced or something? I appreciate it if you can point me to the right direction.

Thank you

Cubaski

Sorry, been too busy with work to check this forum. I had a similar problem with the fog lights on my 90 LS during the last few years I owned it (sold it in 2003). The repair shop that fixed the fog lights about once each year indicated that the problem was caused by corrosion. Problem is ... I never asked exactly where the corrosion was. They polished it off every so often and got the fog lights working again. I think I was told that a new "fuse block" of some sort would eventually be required to fix the problem but I don't know which one. I'm guessing that the current owner of my 90 LS has solved the problem since he fixed other odd problems. I'll try to ask "Tobywan" if he doesn't see this thread and reply.

[cubaski]

Jim,

I've been trying to resolve a power issue with the fog lights on my 92 ls400. I tested the light conducters and fouond no power, I then tested the fuse that's under in the cluster pannel and theres power but not circulating through to the lights. Is there a breaker or a wire that this particular model suffers from being replaced or something? I appreciate it if you can point me to the right direction.

Thank you

Cubaski

Sorry, been too busy with work to check this forum. I had a similar problem with the fog lights on my 90 LS during the last few years I owned it (sold it in 2003). The repair shop that fixed the fog lights about once each year indicated that the problem was caused by corrosion. Problem is ... I never asked exactly where the corrosion was. They polished it off every so often and got the fog lights working again. I think I was told that a new "fuse block" of some sort would eventually be required to fix the problem but I don't know which one. I'm guessing that the current owner of my 90 LS has solved the problem since he fixed other odd problems. I'll try to ask "Tobywan" if he doesn't see this thread and reply.

Thanks for your reply, I actually found the problem. I was not aware that there was a separate switch for fog lights. Thanks

[shrekheat]

Had the same problem with the reverse light coming on and then down shifting. Read the post on how to fix and now the problem is gone. I am very thankful for the help the lexus owners club is the shhhhhh******ttttttt. Thank you

Jason

[Michael's 1994 ls400]

I want to thank everyone for the amazing help I have received with my 1994 LS400.  I just love the car and had no idea so many others did too.  I completed the repair in which my dash reverse indicator light was coming on and the car was down shifting every time I hit the brakes.  I did in fact find the broken white wire in the trunk hinge wiring loom and lengthened all wires to allow more freedom of movement.  I don't how I would have found the problem within your help.  Thanks again for this wonderful community.