Brake Light Warning Issue

[intellivised]

OK. So I've done my homework already and checked up and wanted to get an opinion or two before I proceed.

My car (92 LS400) is starting to do that thing where the 'brake light out' light comes on after starting up the car and then stays on. At first it only did it occasionally, but now it's a full time deal. I searched on the forums and found some similar problems and even went over to this link:

http://www.lexls.com/tutorials/lighting/bulbout.html

And checked it out. I'm not getting any of the other weird behavior, just the bulb out light (and I have no bulbs out, I already checked). Maybe that's on its way?

My main two questions are:

- I'm a horrible solderer. I know enough about electrical equipment to spot a loose or damaged connection but shouldn't be allowed to touch anything with repair in mind with a ten foot pole. I'll probably recruit a friend to do it. I have a guy who does all my guitar pedal work, I'll probably recruit them for this. I just need to know how to get to the harness to have a look - any tips?

- Is this something that'll make my car unreliable for long trips? Like the computer being erratic effecting braking, etc. My band is playing down in Denver (about 2 hours) this Friday and I'd like to be able to drive a carload of friends that want to go; but I don't want to put anyones safety at risk.

This explanation certainly makes sense since my car is a 1992 and ever since my band started I went from never using the trunk to always using the trunk - guitars and amps and the occasional bass player have ridden back there. So... what do you all think?

[90LS400Lexus]

Hi.

My "brake" light is on as well, but its my understanding that the 1990-92 models dont have a "brake light/tail light" burned out warning light. I have been told that was for brake failure only and if its staying on, then its an early sign that the alternator could be failing, probably due to power steering fluid leaking into it. My brake light is sometimes not on, sometimes dimly illuminated and sometimes nearly at full illumination. I do have two brake lights out and one taillight, but since the light is sometimes not on, then its not indicating brake light failure.

I am going to get one of my owners manuals out and see for sure whats going on with this light.

[intellivised]

Hi.

My "brake" light is on as well, but its my understanding that the 1990-92 models dont have a "brake light/tail light" burned out warning light. I have been told that was for brake failure only and if its staying on, then its an early sign that the alternator could be failing, probably due to power steering fluid leaking into it. My brake light is sometimes not on, sometimes dimly illuminated and sometimes nearly at full illumination. I do have two brake lights out and one taillight, but since the light is sometimes not on, then its not indicating brake light failure.

I am going to get one of my owners manuals out and see for sure whats going on with this light.

I've actually read the owners manual when this first came on and the light that I'm talking about looks like a car (orange) with little lines coming from the back, and I *remember* reading in the manual that it was a brake light out indicator. I can't be quoted on this, I need to check to make sure.

The interesting thing is that this has happened before and then it goes away, but it's been happening a lot more. I came home from band practice and the light didn't come on - and the only thing different about the car recently is that it sat out in the rain for a day; it's finally dry. All my rear lights work. I'm tempted to think that it's something to do with moisture and the wire harness. I'm still open to ideas though.

[curiousB]

Maybe a slightly corroded bulb socket? That could make the connection intermittent. If the bulb is open circuit the brake light out circuit will trigger. Maybe just take out the brake bulbs, clean up the base with some steel wool or emery cloth. If you can scrub the inside of the socket with a small wire brush even better. Then reseat the bulb. Just a guess but wouldn't be a chore to try.

[90LS400Lexus]

I've actually read the owners manual when this first came on and the light that I'm talking about looks like a car (orange) with little lines coming from the back, and I *remember* reading in the manual that it was a brake light out indicator. I can't be quoted on this, I need to check to make sure.

How strange... I have never noticed this light on the dash of my 1991, or my old 1990 LS400. Maybe it was added in 1992? I didnt think to look in my owners manual.... let me see if I can find it.

[90LS400Lexus]

Well, i'll be. I found an old manual that I had from my old 1990 LS400 and sure enough, there is a "rear light failure" warning light listed in there, I never seen it come on in my old '90 LS or my current '91 LS. Obviously that light itself was/is burned out on BOTH cars. Strange I was told otherwise that these cars didnt have this warning light. Guess I believed it since it seems they dont work on mine anyway. <_<

I've actually read the owners manual when this first came on and the light that I'm talking about looks like a car (orange) with little lines coming from the back, and I *remember* reading in the manual that it was a brake light out indicator. I can't be quoted on this, I need to check to make sure.

How strange... I have never noticed this light on the dash of my 1991, or my old 1990 LS400. Maybe it was added in 1992? I didnt think to look in my owners manual.... let me see if I can find it.

[intellivised]

Maybe a slightly corroded bulb socket? That could make the connection intermittent. If the bulb is open circuit the brake light out circuit will trigger. Maybe just take out the brake bulbs, clean up the base with some steel wool or emery cloth. If you can scrub the inside of the socket with a small wire brush even better. Then reseat the bulb. Just a guess but wouldn't be a chore to try.

This also seems plausible. I'm going to keep the car until at least fall, so this might be a good mid-June project when my band the month off and I actually have a weekend to myself.

Thanks! Anyone know of any handy guides for where/what lights to get? I have to order some of the amber/yellow lights for the front, so I might as well order a bunch of them together.

[fencera]

Maybe a slightly corroded bulb socket? That could make the connection intermittent. If the bulb is open circuit the brake light out circuit will trigger. Maybe just take out the brake bulbs, clean up the base with some steel wool or emery cloth. If you can scrub the inside of the socket with a small wire brush even better. Then reseat the bulb. Just a guess but wouldn't be a chore to try.

This also seems plausible. I'm going to keep the car until at least fall, so this might be a good mid-June project when my band the month off and I actually have a weekend to myself.

Thanks! Anyone know of any handy guides for where/what lights to get? I have to order some of the amber/yellow lights for the front, so I might as well order a bunch of them together.

Hey, I have a 90 and had a similar problem before with my car. The light out dash light kept coming on and one of my bulbs was intermittent. Or so I thought...

It took a long time and many swapped bulbs, but somehow a portion of my wiring harness was simply developing too much resistance. I had cleaned both ends of the socket (make sure you do this-- just take off the tail lights and spray/scrub connectors as previously suggested), changed to 1157 bulbs instead of the 1157LL bulbs (they have some sort of different resistance I thought might solve the false reading) but in the end, my wires had simply worn out. I asked someone on ebay who was parting out a car to list the section of wiring and picked it up for under $10.

I guess this wasn't that helpful other than to give you another idea of what might be wrong... Good luck narrowing it down! (oh and it's not a problem for long trips and I wouldn't try to solder anything other than a splice... the connectors should work if they are clean!)

[90LS400Lexus]

Well.

I wonder what the chances are of having TWO LS400s, and both having this "rear light out" warning light itself burned out? <_<

[curiousB]

I'm not sure how wires "wear out". Maybe if they are in a door hinge and subject to continual flexing then they can break. In this thread these wires are stationary and not constantly moving. Connectors can get dirty and oxidize limiting a good connection (adding resistance). So I would look to junction points before I'd start changing out wiring harnesses. Clean bulb sockets, clean harness connector pairs and so on. Pick up a can of spray on contact cleaner.

[jeffls400]

I replaced my instrument cluster recently, and the LED for the brake bulb malfunction that projects down on to the cluster is out...need to go pick some up from the junkyard.

I lost all brake lights a couple years ago...the culprit was the lamp failure module mounted in the trunk.

See my post

[90LS400Lexus]

I replaced my instrument cluster recently, and the LED for the brake bulb malfunction that projects down on to the cluster is out...need to go pick some up from the junkyard.

I lost all brake lights a couple years ago...the culprit was the lamp failure module mounted in the trunk.

See my post

Thanks. I am assuming that only the outer black housing has to come out to replace that bulb?

[Csosz74]

Hey, just a thought...

I had the same problem with the yellow taillight indicator. It came and just went away, all my lights worked fine.

But I had a small, but continuous leak from the power steering pump, which finally ruined my alternator.

So just for a quick look, check the P/S pump for leaks and the alt.

A

[90LS400Lexus]

Hey, just a thought...

I had the same problem with the yellow taillight indicator. It came and just went away, all my lights worked fine.

But I had a small, but continuous leak from the power steering pump, which finally ruined my alternator.

So just for a quick look, check the P/S pump for leaks and the alt.

A

Not sure about the others, but I have a moderate PS fluid leak... win the lotto, I might fix it. <_<

[curiousB]

Not sure about the others, but I have a moderate PS fluid leak... win the lotto, I might fix it. <_<

I saw somewhere someone made up a shield to stop the PS fluid from leaking onto the alternator. If it’s tough to fund a PS replacement then you might as well avoid compounding your problems by having to replace the alternator too.

[90LS400Lexus]

Not sure about the others, but I have a moderate PS fluid leak... win the lotto, I might fix it. <_<

I saw somewhere someone made up a shield to stop the PS fluid from leaking onto the alternator. If it’s tough to fund a PS replacement then you might as well avoid compounding your problems by having to replace the alternator too.

Yeah, I have seen and heard about that, but have no idea how to properly go about making one or how to install it. Detailed instructions seem to be unavailable. Lexus should have put one of these on from the get-go from the factory... had they known how crappy their power steering pumps were going to be, perhaps they would have... or not. I think they enjoy seeing poor people struggling to service their old Lexus cars. ;)

[VBdenny]

but its my understanding that the 1990-92 models dont have a "brake light/tail light" burned out warning light

Yes they do. There is a light that indicates when a bulb is out. The BRAKE light indicates some type of problem in the brake pressure system, or that the parking brake is partially engaged. I would wiggle the parking brake around and see if it goes off. I had one occasion where the brake light cmae on and it was because the Ebrake pedal was just slightly engaged. Check the fluid in your master cyclinder and see if both sides are full.

[90LS400Lexus]

but its my understanding that the 1990-92 models dont have a "brake light/tail light" burned out warning light

Yes they do. There is a light that indicates when a bulb is out. The BRAKE light indicates some type of problem in the brake pressure system, or that the parking brake is partially engaged. I would wiggle the parking brake around and see if it goes off. I had one occasion where the brake light cmae on and it was because the Ebrake pedal was just slightly engaged. Check the fluid in your master cyclinder and see if both sides are full.

Yeah, I was curious, so after someone posted this, I looked in a owners manual I had for my old 1990 LS400 and it does show the warning light. The reason I thought they did not have one, is that years ago, someone on this very site had a thread going that these cars didnt have one, which I thought was odd, because even my old '87 Camry had one. Also, the fact that this warning light was not only burned out on my old '90 LS400, its also out on my current '91 LS400, so I just never thought much of it. I have two brake lights and one taillight on my LS, so I know if that light worked on my car, it would be illuminated. I guess with 6 taillights/brake lights that more lights tend to go out and that light is probably on alot, hence the bulb blowing out quicker than others. ?

I am suprised that my "low coolant" warning light bulb has not burned out yet... the sensor is bad and the light has been on ever since I have owned it... coming up on two years.

[intellivised]

but its my understanding that the 1990-92 models dont have a "brake light/tail light" burned out warning light

Yes they do. There is a light that indicates when a bulb is out. The BRAKE light indicates some type of problem in the brake pressure system, or that the parking brake is partially engaged. I would wiggle the parking brake around and see if it goes off. I had one occasion where the brake light cmae on and it was because the Ebrake pedal was just slightly engaged. Check the fluid in your master cyclinder and see if both sides are full.

Yeah, I was curious, so after someone posted this, I looked in a owners manual I had for my old 1990 LS400 and it does show the warning light. The reason I thought they did not have one, is that years ago, someone on this very site had a thread going that these cars didnt have one, which I thought was odd, because even my old '87 Camry had one. Also, the fact that this warning light was not only burned out on my old '90 LS400, its also out on my current '91 LS400, so I just never thought much of it. I have two brake lights and one taillight on my LS, so I know if that light worked on my car, it would be illuminated. I guess with 6 taillights/brake lights that more lights tend to go out and that light is probably on alot, hence the bulb blowing out quicker than others. ?

I am suprised that my "low coolant" warning light bulb has not burned out yet... the sensor is bad and the light has been on ever since I have owned it... coming up on two years.

My sensor went a few months ago. I'm tired of looking at the Parthenon of Doom. I spent $40 on a diagnostic and quite a bit more on some Toyota coolant before I figured it out that it was, indeed, just a broken sensor. My landlord was real happy with my Lexus peeing coolant over the driveway because I had misgauged the overflow valve.