skperformance

iTrader: (6)

It makes sense GRAND_LS 4 now that you mention it. Problem is i think mine is much dimmer than it should be , I mean i am straining to see the dash at night. My lighter is brighter on the gauges than the lighting.
Options so far is to have a second source light up the sensor like a small LED .
Disconnect the senor with unknown effects.
I'll call some guys at Lexus head office and see if their is a fix.
I am still waiting for the low idle update on the ECU for my LS as well from them.

Frankdorn

iTrader: (7)

Yup--they're about 1/8" diameter CCFL bulbs bent around most of each gauge. Where could these be re-made? A neon sign store?

lexus ASM

I think one could make a ring of LED's modeled after the shape of the cathode tube. That should work.

I'll take my speedometer out and try this sunday.

djspawn00

do a DIY write up, or at least take pics

Frankdorn

iTrader: (7)

Yeah--PLEASE do this. I was also looking for an LED string or rope lighting of sorts, but they either couldn't be cut-to-length, or the spacing between lights was too far. I'm not sure I have the expertise to use individual LEDs strung together.

skperformance

iTrader: (6)

Well after grand's explanation , i took an LED key chain and aimed it at the solar sensor right in front of the driver on the dash by the windshield edge.
It got bright and i could see again at night , After turning the key chain on and off a few times , the back lighting stayed brighter until i got home.

HEY HEY , i started the thread , i want first dibs on a fix, lmao .

lexus ASM

Ok I pulled out my cluster today and took it apart... This task is going to be a tough one. Ill let the first picture explain.

What you see ( the spiral coated tube) is one of two cold cathode glass tubes that cup the tachometer and fuel and temp gauges.

skperformance

iTrader: (6)

Get those cheap aftermarket rope/string lights that are thin and run that beside the lighting so it adds to it all the time with the ignition.
$20 and be done.
I can;t find any to link to on the web.

lexus ASM

i've been researching that already, its not that simple, the space the ccfl tubes occupies is designed for its diameter. There is not enough room to add any other lighting material within the confines of that space.

Im trying to find a junk yard cluster with which I can test fit different LED's to determine the best set up.

sakataj

iTrader: (182)

ok this has peaked my interest again

BCP43002

A wild guess. Would removing the tubes and making the backing more reflective work or are the tubes not bright enough?

skperformance

iTrader: (6)

I understand about space but the rope lights are tuly 1-2mm thick if that. It is about the thickness of a rubber band and looks like it could be wedged into the inside curve of the CFL tube.
Finally i found a place .
http://www.neonstring.com
A little pricey compared to buying a small unit complete for $20 like i used to wholesale.
If anyone else finds something it goes under the name " neon (rope OR string) light"

JC&AB

Just a question. If the display is OK in daylight then it must be working properly? If it was not providing enough light at night, then wouldn't it be worse in bright sunshine, so you could not see it at all? If it goes dim at night then the circuit that dims the light must be at fault not the light itself.

I'm not sure how Lexus dims the light, but its not simple resistance dimmer. Domestic CCF lights use a pulse signal system that cuts out some of the pulses to dim the light. This is so fast that the eye never notices it. The brain will average the pulses of light and will cause us to 'see' a brightness level lower than what we normally perceive to be full-on. As long as the process is fast enough, the eye and brain will continue to average the result. This produces very effective dimming down to 1% of full brightness.

So the question to any electronics experts out there is how do we check whether it is the sensor or the dimming circuit?

skperformance

iTrader: (6)

The circuit works just is inadequate at night for me.
With it being a cycle lighting system it is even more reason i don't want to touch it.
To change the actual dimming you need to
manipulate the solar sensor eye with more light
add voltage between the sensor and the controller to tell it more light is there electrically.
add a switch with variable resistance to control just the dash back lighting with a twist as you want any time.
I personally like just adding a secondary lighting structure to supplement the original. Easy to install , less messy it works. Plus you can pick a new colour if you want.

djspawn00

I don't think those neon string lights would emit enough light... even when used with the existing ccfl it probably won't be much of an improvement but I'd be glad if someone proves me wrong... that would mean we have options now!