IBY

HI guys, i am in the market for a 1998-2000 LS400 and found one, the problem is the guy selling it just told me that the airbag light came on for some reason, the day i was supposed to go and check it out. Overall from what the owner told me, the car has been well maintained and runs well, it has 180,000 miles on it, my question is what could be the issue with the airbag light? The owner runs a car repair shop and told me that he cant read the module, i'm guessing he means the OBDII reader port. Would it be a bad idea to purchase the car with the airbag light on? I would have to drive about 6 hours to go and check it out. The owner told me he brought it out of storage, so i'm not sure, what do you guys think is the issue, thanks!

CELSI0R

I don't know if it changed after 1994, but I know that on the first-gen LS 400s, the air bag light is triggered if the instrument cluster warning lights are removed, if the airbag goes off, or if there is some other error code in the SRS system from a triggering event. Chances could be that the cluster was worked on without the battery being unplugged, causing an error code to be thrown.

The only way to verify the issue is to read the SRS codes from the OBD-II port on that car. If he can't read from it, that's a bit strange... I have heard of bad ECU capacitors creating problems with OBD-II readers on 1995 models.

If you want to take a chance, you can risk the trip and bring a scanner with you, if you have one.

spuds

Pass.You are just buying someone else’s problems.Plenty other cars out there.

PhilipMidd

Interesting - I have a similar issue.
My car has issues, but the air bag light has always gone off once the car is started.
I did a bit of work on the power steering pump (that damn vacuum switch) when I accidentally flashed my spanner across the alternator + and earthed it out.
Bang went the main alternator fuse. Oops forgot to disconnect the battery. One large box type fuse later and we are all up and running again. However now my Airbag light stays on 100% of the time. ?
This only happened yesterday, so today I'm going to disconnect the battery for 1/2 hour in the hopes that that will clear any errant fault code that may have poped up due to the short. For your situation, I'm not sure how much of a good idea it is to just try and clear all codes and see if it pops up again, but that's what I intend to try first. Don't know how long you have to disconnect battery to do this, but assume 1/2 hour is enough. Can anyone correct me if I'm wrong on this? Or is it better to just pull a fuse for an amount of time?
Just thinking, before you commit to go there, you could get the owner to do that to see if the error light goes away, that is if you havn't already passed on it or purchased it.

TrapMaster

Disconnect the battery if you're trying to actually reset codes. Some folks like to disconnect the battery and then pump the brakes a few times to help drain any remaining energy (the idea being the tail lights will drain any remaining power). Its also possible you shorted something out in either the ECU, air bag module, or a sensor.

OP: I would take the car someplace else and have it inspected before purchase or at the very least run a vehicle background check. Its always possible this was caused by some sort of accident in the cars past. If you do go look at it carefully inspect the front end for sure. Look for signs of repair work, overspray from a repair, odd welds, poor panel gap, etc.

PhilipMidd

Thanks. Battery is off at the moment and I had shorted the + battery lead to ground to try and do exactly that, but I just run outside and pumped the brakes. LOL. I feel like such a noob with this car. I've always done my own mechanical work but I've always had very basic cars from the 60-90's where problems are obvious and easy to diagnose. no computers, hardly any electronics (mainly older diesels etc).
This car has been an eye opener!

Thanks.

TrapMaster

No problem man. Really a lot of the problems you'll run into with modules while working on cars comes down to accidentally damaging them with an electrical surge of some kind. Overloading a circuit with a mod, damaging a harness, or other accidental shorts. I've gotten into the habit of disconnecting the battery any time I'm working in the bay or around a lot of wires ever since I fried the fusible link on my Z in an accident similar to what happened to you.

PhilipMidd

Sounds like good advice. I'll keep it in mind.
Well, battery disconnected for 2 hours and Air Bag light still on. But I'm not sure it cleared anything cos the auto steering wheel location thing still remembered where I put the steering wheel.
Going to ignore it for now... there are more pressing things that need to be addressed on the car. I'll come back to it later.

deanshark

Disconnecting the battery doesn't clear the codes for the airbag. This is the procedure: http://www.lexls.com/tutorials/light...rbaglight.html
I think the memory seats and steering wheel stays even if you unhook the battery.

PhilipMidd

Thanks. I'll try this when I get a chance tomorrow. I'll let you know how I go.
...
It looks like my diagnostic link (TDCL Port) is located on the Engine (Left hand side front). Well, it means that earthing the wires will be a lot easier. I'll just have to have someone in the car to tell me if the light flashes fast of just flashes out a code (presumably 4 and 1).
It looks like its been covered in grease that's now combined with water, but I'll give it a good clean and repack with fresh grease.

TrapMaster

This is good to know, thanks.

Does anyone know if there is different information available from each diagnostic port or is it all the same? Like is the under hood port a Toyota specific port or is it the same as the OBDII port under the dash?

deanshark

On 90-94 There are 2 TDCL ports. 1 in the engine bay and 1 behind the lower dash panel under the steering wheel. Not sure how the OBDII works on 95 and up. I never owned a vehicle newer then 94. (I like living in the stone age. ) The link I posted is for 90-94. I just realized OP was talking about 98-00.

IBY

Hey guys, quick update. i talked with the guys selling the car over the phone and they said that the airbag sensor went bad and that they would lower the price of the car if i bought it, in which they would also send me a used sensor that worked. Or if i wanted they could replace it themselves for a fee. So i had them buy it and install it, but it has been taking a while for them to receive the sensor. What i was wondering was, if i did buy the car before they installed the new sensor, because i need to get a car very soon and i can't really wait anymore, also maybe i could find a cheaper price for someone else to install it, if i have to. Does anyone know the location of the airbag sensor on 1998 LS400?

spuds

Do keep us updated.

spuds

Yup,I feel like that too.