Lexus IS300 HID level error

[Krys Kozlowski]

Symptom: The HID (high intensity discharge, or sometimes Xenon head beams) system error pops up on he dash, headlights point down quite a bit, do not auto adjust anymore.

Solution: Toyota designed a rather simple yet for some reason very expensive system to automatically adjust the beam height of their HID system. On the driver side, you will find two sensors on the suspension, near the body, inside the wheel well:

For my procedure, I started with those.

Remove the wheel (either driver side front or rear), and you will find something like this:

The marked area (thank you, my.is forum) is the sensor in question. Take off the screws, detach the wires, and take it out of its housing. You should end up with something like this:

You may want to open the sensor in a clean surrounding. It’s essentially a potentiometer like we used to have in the good old analogue mixing consoles (sigh). The two most common problems seem to be either dirt / dust on the circular black bit on the left of the picture and perhaps on the teeth bit on the right. You can clean that off with cleaning alcohol or better something that isn’t aggressive on coal conductive surfaces. OR it could be the seal ring you find when you open up the sensor assembly. You may be able to get a new seal for a few cents from your local autoparts store (is what I did), or try fixing it with leak stop of some sort. I personally went for the new seal though.

The second system that may give out on you is the actual activator / motor assembly located underneath the individual HID lamp in the front.

I took off the front lip / bumper assembly and took out the HID lamps themselves. Do be absolutely sure there is no power on the system when handling HID wiring. I think they can go up to 40.000 Volts and can be QUITE DEADLY. So handle with extreme care. Before working on an HID system, I like to detach the battery, then turn on the front lights. This way the lights will not come on of course, but the capacitors inside will discharge fully before you even touch anything.

Once you get the lamps out, you will find a box underneath them. That one is the ballast, for when your lights don’t turn on. On the inside bit, you will find an actuator, I do not quite remember where it was, but it should be a round electrical motor. You can test it for a short or straight forwardly replace it. You may be able to take it out without pulling the whole lamp assembly, I needed to get to the ballast as well, so for me it was easier that way.

Cheers

Attachments:

• IS300heightsensorloc.png
• IMG_4064.JPG
• autoleveling_sensor_6.jpg

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[Krys Kozlowski]

Again the google helped me out with a pic for the actuator / motor!

I believe, it is this round bit on the bottom:

For me, all worked out fine with just the height sensors. If you want to go through the entire chain top to bottom, the system wiring also includes the IG fuse, two beam ECUs inside the ballast (I think), and a beam level ECU.

Looky here:

Attachments:

• is300lamp.JPG
• IS300beamcontrolECUfuses.png
• IS300beamcontrolECU2.png

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