Change Bulb In Headlight Level Switch To LED
09/01/2007
I noticed that the headlight level switch control was not illuminated. I ordered a replacement bulb (which is a standard filament type) from Toyota at £4. I subsequently thought about changing the bulb to a white LED. To do this follow these steps:
1. Remove the switch from the dashboard (below and to the right of the steering wheel next to the security LED).
This can be quite fiddly. It is in fact clipped top and bottom, so its easier to stick a penknife or a flat-head screwdriver in at the top then twist, then at the bottom then twist, then remove it from the sides.
2. Remove switch and disconnect from the wiring.
On one side of the white connector there is a clip that must be depressed so that the unit can be disconnected from the wiring. I found this quite stiff on mine.
3. The front face is clipped to the main body of the switch at the top and bottom. Unclip this again using a penknife or flat screwdriver.
4. Unclip the side face from the main body (held by 4 clips)
5. Remove circuit board from casing. This is held in by 2 clips at the white base connector.
6. Remove the stock bulb from the circuit board. This is done by a quarter twist. The stock Toyota part number for this bulb is 90010-08100. Cost at this date was £3.50 (plus VAT). If you simply wish to replace the current bulb with a new stock one, just replace and re-assemble and reconnect the unit back.
7. If you wish to replace the stock bulb with an LED then it may be possible (i have not done so myself) to do so without soldering but you would need a 12V LED. If you have one, you can still of course go the soldering route below if you wish (but without the need to include a resistor), but it may be possible without soldering by disconnecting the bulb from its blue plastic base, feeding the LED legs through the holes and bending the leg wires around the plastic as per the stock bulb. Just ensure the correct legs are connecting to the positive and negative parts of the PCB. (The positive leg of a new LED is the long leg).
The bulb connects to 2 semi-circles on the circuit board. The correct leg of the LED must connect to the correct part of the PCB.
Most LED's are approx 3V. You can get 12V LED's which will make things easier, but I already had lots of LEDs that I bought off eBay (nearly all off eBay are 3V with resistors), so i decided to do it this way as, after examining the assembly, I saw that there was enough room to also house a resistor. It can be put inside the circular level adjustor switch itself.
8. Cut the negative leg of the LED (the short one) to size and solder it to the LED to the negative copper semi circle.
9. Measure out enough of the resistor leg to make contact with the positive side of copper, and to be able to bend the leg around so the resistor hangs down into the switch itself. Unlike LED's it does not matter which resistor leg you use. Solder one leg of the resistor to the positive copper semi circle, then solder the other resistor leg to the positive leg of the LED. Cut away any excess leg stalks.
10. You now have a nice new LED. Ensure placement of the resistor is roughy as shown in the picture. This is so that it fits in the inside of the circular adjustor switch for when you fit it all back together again.
11. Clip the casing back together.
12. If you went the LED route then I recommend sticking some reflective material over the hole that the bulb is exposed to. This is because LED's also emit light from their base, and this will throw more light back into the switch unit itself. I stuck some silver foil onto some adhesive tape, and covered the hole with it. Please note that if you do this that no parts of the LED legs are sticking up through the hole so as they do not make contact with the foil, so I would also recommend some clear plastic between the hole and foil.
Job done!
