Headlight Auto Levelling System

Lexus-IS · December 21, 2016

Does anyone know which fuse and what location fuse is for the headlight levelling system for a Xenon IS250? mine has stopped working all of a sudden and i think maybe a fuse.

madasahatter · December 21, 2016

Maybe one of the levellers has given up the ghost. If its a fuse should be in the handbook.

Britprius · December 21, 2016

By far the most common reason for failure of the Toyota/Lexus light leveling system is the height sensors on the suspension. Sometimes it is the actual connecting rods that snap due to seized end ball joints. Other times it is due to water entering the variable resistors. Both can be repaired without to much difficulty. New ones are expensive "circa £200 each".

John

normski2 · December 21, 2016

There are 2 sensors. 1 at the front and 1 at the back. These pictures should help you.

Mine went screwy a couple of weeks back after discovering a horrendous pothole in the dark. The light beam dropped there and then and would not level afterwards.

Set up a image screen at work and adjusted both sides and now all is good again.

If you need the set up imaging I have it on file on my PC. Just shout.

Lexus-IS · November 27, 2017

Thanks for those diagrams normski2, the diagrams show that both front and rear height sensors are on left passenger side is that correct?

Lexus-IS · November 27, 2017

Can the sensor be inspected to see if they are damaged without removing the wheel? Or is removing the wheel a requirement?

normski2 · November 27, 2017

You can turn the wheel to get a look at the front sensor.

You can see the rear by crawling under but its a bit tight. Putting one wheel up on the kerb can help.

headlight aim

Headlight_aim.pdf

Mark out the grid on a board. Find the two adjusters on each headlight. The one at an angle almost under the wing is the hardest to find. Use a 150mm pozi 2 extension in a Battery drill on slow speed. At least that's what i did.

There are a couple of useful guides on the US forum.

normski2 · November 28, 2017

These posts are useful too.

Sorry its taken a while to come back to you ....looks like my graphics card on my PC at home has died. Thankfully I have the trusty steed at work!!

http://www.lexomans.com/manguide-559.html

https://www.clublexus.com/forums/es-5th-gen-2007-2012/318952-diy-headlights-adjustment.html

Lexus-IS · November 28, 2017

Great info, thanks. Are the height sensors on the passenger side?

normski2 · November 28, 2017

The rear one is definitely on the passenger side. I remember that well as I crawled under the car to look at it.

The front...I honestly can't remember. I think it was passenger side. It's pretty obvious when you see it. There are photos of them on the US site.

Both mine were fine. Solved the problem with the beam adjuster cog wheels. Also ended up with much better beam pattern and much improved road illumination.

normski2 · November 29, 2017

Just been out to the car in tea break and taken some piccies.

Both sensor levelling brackets are on the passenger side.

FRONT SENSOR

REAR SENSOR

Best shot I could get from lying on the road!

Hope that helps

Lexus-IS · November 30, 2017

That's great, many thanks.

Lexus-IS · December 18, 2017

The aiming guide says to turn the vertical adjustment screw clockwise to make the beam higher. When I do this the actual projector thing inside the headlight goes and faces more towards the ground. Is this how it works? The more it faces the ground the higher the beam? I would have though the other way round

Lexus-IS · December 18, 2017

So i jacked up front passenger side to inspect the height sensor. With the wheel off and car lifted, am I supposed to be able flex and move the arm up and down? I thought i'd inspect it and silly me I decided to loosen that nut arrowed in the picture. My plan was to remove that one and the one one the other end. But now that nut is just spinning and not tightening nor coming out. The bolt that the nut attaches to where does that go? has it broken the sensor?

Other than that the links of the mechanism all seem connected. So unless the actual sensor is gone. I will have to inspect the back one too. But now concerned with a loose wobbly front mechanism as i cannot tighten that nut. any ideas?

Farqui · December 18, 2017

Oh dear, can you get behind the arm to lock the shift with some long nose pliers AND then try to gently tighten the nut?

So the arm didn't move before you removed the nut?

Farqui · December 18, 2017

If your sensor is like this then you should be able to get a spanner on the back to hold the shaft

Lexus-IS · December 18, 2017

Farqui, thanks. The arm didnt move at all. I will try and remove the entire bracket tomorrow and bring it indoors and have a closer inspection. I watched some youtube videos of some sort of corrosion that happens inside the sensors. These sensors are ridiculously priced.

Farqui · December 18, 2017

Okay, good luck

Lexus-IS · December 18, 2017

I read that if the nut is spinning then might mean the rotational sensor in the unit is screwed. Wonder how it is attached on the sensor itself and if it is repairable. Anyone know?

normski2 · December 19, 2017

I've not had to work on the sensor itself before, but I bookmarked this for future reference as you never know!!

Have a scan through this it may give you some pointers. Not the same model but it would not surprise me if some parts are common across the range.

Lexus-IS · December 19, 2017

Today, I replaced the complete front sensor which i got from a scrap yard. I inspected the new and it looked in good condition and tested for resistance across all the pins. I got it as a complete piece with the brackets and rods. Also noticed on of the pins in my old one had slight bluish stuff almost like when a Battery leaks and you get that residue. I cleaned the pin up. I was hoping that would do the trick. But to my disappointment I turned the car on and put headlights on and the lights are just not going up and down like they used to. They used to self-calibrate and I used to be able to noticed it before.

So I moved on to the rear sensor. The rear sensor looked like it was in really good condition. I removed the entire unit to inspect. I tested it across the pins for resistance. It all measured with some resistance. So I have no idea what is wrong, shall I change the rear one too? One thing I did notice on the rear one however is that you see the short rod with a ball joint on each side, is it supposed to move around freely on both ends? I would have thought so because isnt that the purpose of a ball joint? For some reason one ball joint was moving around and the other was completely seized. The rubber around both ball joints seems to have deteriorated. But with the single ball joint I assume it can still move up and down. So do you think the ball joint might be preventing the sensor from moving in the correct way?

Lexus-IS · December 19, 2017

I was thinking could it be the headlight itself but then that cant be because both of them stopped at the same time and they both not working. So seems like whatever is supposed to send the power to control it isn;t because of certain things

madasahatter · December 19, 2017

On 21/12/2016 at 2:49 PM, Lexus-IS said:

Does anyone know which fuse and what location fuse is for the headlight levelling system for a xenon IS250? mine has stopped working all of a sudden and i think maybe a fuse.

Is your afs light on the dash?

is200 Newbie · December 19, 2017

Have you tried to reset the ECU - Battery lead off for half an hour or so and reconnection.... Worth a try, costs noting other than resetting windows etc

madasahatter · December 19, 2017

24 minutes ago, is200 Newbie said:

Have you tried to reset the ECU - battery lead off for half an hour or so and reconnection.... Worth a try, costs noting other than resetting windows etc

That is a good idea, i watched a video of a lexus says its the rear which is the main one. Both knuckle joints should also be able to swivel freely.