steviec_lj

Known issues to look for;

Replacement windscreen - They leak if not fitted correctly and cause no end of problems.

Do the headlights work correctly, or has the circuit been modified? If its modified, it will cost to get it fixed as the Theft ECU is at fault.

Stainless Exhaust system, yes they have one, but as most are now 11/12 years old, they WILL be getting tired, has it been replaced?

Alternatively, stay away. Problems they throw up are costly to repair if you are a dealer only person and hate getting your hands dirty.

See here, 99% of the information given on this forum is absolute crap...

http://www.lexusownersclub.co.uk/forum/index.php?showtopic=28384&st=240&gopid=757308entry757308

Right, I got bored of quoting all of the misleading information in the thread, so here is what WILL sort out the "Headlights remain on after switching the ignition and lighting circuits off!" issues.

Quotes from the topic;

on your light switch, does this happen on auto aswell ?

theres been a case where its been the switch itself, but as you mentioned about dvd etc then best to go over the wiring from the fuse box -

It doesn't matter what position you put the switch into, the lights remain on when the ignition is off. Also, after some time the Headlight Control Relay WILL start to buzz as the voltage causes the coil to become temporarily energised. The switch IS NOT at fault!

That sounds like a relay whose contacts are welded together (amongst other things), could be 2 relays with welded contacts (lights on and dip/main) or permanently energised.

Might be worth taking the lighting relays out until you find the problem.

The relay contacts are NOT welded together, and there is only a single relay which controls the lighting circuits. Taking the relay out will solve the issue temporarily, but this isn't an ideal route!

Misleading information alert:

Note that there is an ecu controlling the lights, all the light stalk does is send signals to the ecu telling it what lights you want on, the ecu then activates the various relays concerned.

There is NO ECU controlling the lights. The ECU you would be referring to is the "Theft Deterant ECU" which controls a number of functions on the Lexus IS200, including but not limited to the lights.

what if you leave the switch on the 'auto' then switch off engine, take key out and open driver door... do they still stay on?

or have you tried cleaning the sensors on the front right corner of the dash (could be covered so lights stay on .... but then agen, should still go off when driver door opened...

puzzling that one... cant help you any further ...sorry mate

Switching to "Auto" and turning the engine off will do nothing to solve the issue.

Cleaning the sensors will do nothing to solve the issue. Removing them from the circuit does nothing to solve the issue.

Hi,

I'm having the same problem. and it only started yesterday. RAC bloke said he has re-booted the system, he thinks its some brain that tells the auto lights to come on. i'll give lexus chester a bell on monday morning to book it in. glad its under a 12 month warranty.

The RAC bloke was along the right lines. The fault that will have come up on his scanner will be something along the lines of "Headlight ECU Programming Lost". This actually refers to the "Theft Deterant ECU" which will have burnt components inside caused by shorting.

Thats right, water/moisture runs down wiring from multiplug at O/S of windscreen, and gets into fuse/relay block at drivers kick panel. Just needs a good blow out and reseal screen at wiring.

Shut up!

we've had a couple of instances where there has been water ingress into the fuse box in the driverside footwell

a replacement fusebox was needed in both instances

Shut up! The fusebox DOES NOT need replacing, Lexus Derby attempted to do this on a family members car, as they could not diagnose the problem fully. There may be oxidisation on some of the contacts, but this can be cleaned and by no means does it mean a costly replacement is needed!

Yep it happened to me ages ago cost me £200 to have the water removed and the fuse box cleaned now after the heavy rain its happened again and im gutted.

Seein more people have the same problem with many ways of fixin it is disheartening as its so expensive goin to Lexus and even they dont know half the time.

Because whoever fixed it for you DID NOT address the route of the problem.

So, you're probably wondering how to solve the issue? Well, thats what I've managed to do on a 1999 Lexus IS200 successfully for the last 2 years.

The replacement part you need is the "Theft Deterant ECU" available direcly from Lexus if you wish to pay through the nose, or you could do what most sensible people these days do, and request one from a salvage yard. They regularly come tested and with at least a 3 month warranty on them, you'll know immediately if it's good or not as it will or won't solve the issue.

Further to this, you also need to have the windscreen removed, resealed and reseated properly. RAC, Autoglass and other major Windscreen Replacement Companies ARE aware of the issue with the Lexus IS200 and the front screen heater connections on the bottom drivers side of the screen.