Sign in to follow this  
RX-Men-8

Load Resistors - The Alternative Way

Recommended Posts

Hi,

As I can't post in the Group Buy threads regarding LED tail lights / brake lights, I'm opening a new one here.

LED lights in tail/brake light draw so little power (current) that the light failure sensor will show a failure in the instrument cluster. For the tail lights this is the orange car-shaped light left of the rpm gauge, for the brake lights it is the red combination light which also works as a handbrake warning ((-)). Commonly this can be remedied by putting a load resistor across the bulb wires so more current is drawn to appease the light failure sensor.

It's a pity the energy saving qualities of the LEDS go to waste, generating a lot of heat in and around the load resistors. Moreover, a light out wouldn't be detected anyway as the load resistor will keep the sensor happy. So why not do away with the light failure sensor altogether.

I have managed this by disconnecting part of the light failure sensor. If you want to do the same, follow these steps, If you have a 1999 model IS200. I can't be sure but quite possibly this is the same on other models of IS200, IS300 or Altezzas.

1. Remove the boot liner at the left wheel well.

Here you can see the left wheelwell in the boot. The light failure sensor is not easily seen as it is at the back of the panel (arrow).

Light_failure_circuit_1.jpg

2. Unplug the connector. At this point the tail and brake lights will not be working.

3. Unclip the purple/green and the purple/white wire from the connector. Use a very small screwdriver to unlock the latch holding the plug in the connector.

Light_failure_circuit_2.jpg

These are the return leads to the orange tail light filure light and the red (hand)brake combination light ((-)) in the instrument cluster. Insulate the ends and

4. Plug the connector back in.

Ready!

To be absolutely clear regarding the questions in the following posts:

- The orange rear bulb out warning will not light anymore

- The red brakelight out / handbrake combination light will only light if you pull the handbrake, but not anymore because of the brakelight issues (LEDs or failures).

This also sorts the high mounted brake light, which is checked by the same light failure sensor. So you can fit a LED there as well (W16W, 955 or equivalent, small fitting) without a load resistor. I couln't find a LED W16W equivalent and modded a 7443 instead.

Cheers,

RX-Men-8

Share this post


Link to post
Share on other sites

nice one gerhard...good technical tip indeed

Share this post


Link to post
Share on other sites

Very good alternative to fitting the load resistors!

Share this post


Link to post
Share on other sites
Moreover, a light out wouldn't be detected anyway as the load resistor will keep the sensor happy. So why not do away with the light failure sensor altogether.

just so we are clear, your method will also prevent the driver from knowing theres a light out, correct...

Share this post


Link to post
Share on other sites

Nice one, does this also remove the handbrake warning light?

No. The hand brake warning works like before. It is triggered by a switch in the hand brake handle and not by the light failure sensor.

Moreover, a light out wouldn't be detected anyway as the load resistor will keep the sensor happy. So why not do away with the light failure sensor altogether.

just so we are clear, your method will also prevent the driver from knowing theres a light out, correct...

Yes. No difference there compared to fitting load resistors.

Share this post


Link to post
Share on other sites

Nice one, does this also remove the handbrake warning light?

No. The hand brake warning works like before. It is triggered by a switch in the hand brake handle and not by the light failure sensor.

We were finding without the load resistors that the bulb out light came on and the handbrake warning light came on.

So just to confirm, even though the bulb out light has now gone, the handbrake warning light still appears.

Share this post


Link to post
Share on other sites

Lexus do a plug in replacement module for when the high level brake light is disconnected

when for example you use a spoiler with LED lights built in

if i had known about this excellent tip , i wouldnt have bothered buying it ....and costing £70 it would have been a lot cheaper :crybaby:

Share this post


Link to post
Share on other sites

Nice one, does this also remove the handbrake warning light?

No. The hand brake warning works like before. It is triggered by a switch in the hand brake handle and not by the light failure sensor.

We were finding without the load resistors that the bulb out light came on and the handbrake warning light came on.

So just to confirm, even though the bulb out light has now gone, the handbrake warning light still appears.

Noooooooo. With this mod all is normal. Except that you don't get any bulb out warning (tail light out) or (hand)brake combination light (brake light out). Of course if you pull the handbrake, that same light still lights/works, but that isn't modded here.

So:

- The orange rear bulb out warning will not light anymore

- The red brakelight out / handbrake combination light will only light if you pull the handbrake, but not anymore because of the brakelight issues (LEDs or failures).

Cheers,

RX-Men-8

Share this post


Link to post
Share on other sites

I have managed this by disconnecting part of the light failure sensor. If you want to do the same, follow these steps, If you have a 1999 model IS200. I can't be sure but quite possibly this is the same on other models of IS200, IS300 or Altezzas.

My Altezza didn't come with any fancy dancy Light out feature..... probably saved another couple of grams... lol :P

Share this post


Link to post
Share on other sites

So does this mean the handbrake light wont work anymore??

Only kidding, I understand perfectly, ingenious tip.........

Share this post


Link to post
Share on other sites

Update: I have the schematics and line drawings of the 1999 IS200, and for RHD models this light failure sensor is not mounted behind the panel on the photo from my LHD model, but more accessible on the front side.

As far as I can tell from the line drawings, anyway.

Cheers,

RX-Men-8

Share this post


Link to post
Share on other sites

Hi all ;)

I found this thread as I was looking for info on this subject, and instead of starting a new topic I would just like to explain my issue and if u can guys tell me whether I have a serious problem or if I can simply solve it the way this thread describes.

I am getting the handbrake warning light on permanently too except in my situation, yes I do hyave load resistors fitted to the brake lights as I have leds in there. This of course causes the orange bulb out warning to light, which has always been the case. I can solve this with 2 resistors on each side but never could be bothered hehe. Now, the handbrake light never used to come on until recently, which is what leads me to believe the LR's arn't at fault. When I raise the HB the light slightly brightens. I checked the owner's manual which says to take the car to lexus asap if this light comes on, however I have no problems with the car. I just recently got it MOT'd no probs. I had the brake fluid topped up, which resulted in the light going off for a couple days. I thought that perhaps this was caused by some moisture or something in the brake fluid. The light is back on, and it's bewildering me.

I think I will reove the LR's I have on at the moment, but do u think this is just a sensor problem or should I be more concerned ? - Any help is appreciated.

Happy new year ! :)

Share this post


Link to post
Share on other sites

finally got round to doing this works a treat

couldnt see how u dissconnected them clips tho i had the smallest screw driver known to man n was tryin to unclip but just was not havin it lost my temper in the end n cut the wire LOL feel bit bad now tho lol

Share this post


Link to post
Share on other sites
I have managed this by disconnecting part of the light failure sensor. If you want to do the same, follow these steps, If you have a 1999 model IS200. I can't be sure but quite possibly this is the same on other models of IS200, IS300 or Altezzas.

My Altezza didn't come with any fancy dancy Light out feature..... probably saved another couple of grams... lol :P

does this mean you do not need to use the load resistor if your car doesn't have this feature

Share this post


Link to post
Share on other sites

id LOVE to no how u unlatched them connectors coz i just cant do it tryed every thing been outside for over an hour and they just will not come out no matter wot i do

wots the secret to getting em out lol

Share this post


Link to post
Share on other sites

Hey there all,

Just thought I'd let you know that I did this at the weekend and it sorted my light issue out a treat. The light also still illuminates when the car initialises.

Also just as an additional note:

I was only able to locate the purple / green cable and not the purple / white cable.

This still removed the light out warning on the dash and has not caused any other adverse problems at all.

My car is a 2002 02 Lexus IS200 Sport for reference.

Regards,

Jamie

Thanks to eXoBeX for directing me to this thread.

Share this post


Link to post
Share on other sites

Nice one dude. I was a little concerned about the load resistors and the heat they give off. If only Id have know this way back when I put the brake pulse LEDs in...

Top tip!

Share this post


Link to post
Share on other sites
I was only able to locate the purple / green cable and not the purple / white cable.

This still removed the light out warning on the dash and has not caused any other adverse problems at all.

Excellent, as I remember, the two wires were next to eachother in the plug, one was for the brake light sensor, one for the tail light sensor. Maybe your car is slightly different, I don't know.

For the ones who had difficulty getting the contacts out of the connector, I'm pretty sure I remember you have to move a plastic locking mechanism on the wire side of the connector. Once that's unlocked it's not hard to pull them out. It's either that or you have to push in the locking tab on the metal contact to move it back.

Cheers,

RX-Men-8

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this