Dash lights will not work if door is closed..... (1 Viewer)

[Snowstorm]

I noticed my dash lights on my 2006 LX were not on. The climate control lights are out and the exterior temp lights are out. But when I open the drivers door everything comes on.

Fuses in engine comp are OK. The light dimmer switch seems to not function. Headlights are set to automatic.

I have not checked the fuses on the kick panels.

With door open all instrument lights work. But when I switch from auto headlights to any other setting everything dims like it should.

All interior lights are working. Door lights, dome light, etc.

Right now I am leaning toward the dash light adjusting switch being bad, but I have not tested it. The door switch was replaced and is not the problem.

Is there one wiring set up for door open and another set up for door closed?

Any comments are welcomed.

 

[Snowstorm]

I noticed my dash lights on my 2006 LX were not on. The climate control lights are out and the exterior temp lights are out. But when I open the drivers door everything comes on.

Fuses in engine comp are OK. The light dimmer switch seems to not function. Headlights are set to automatic.

I have not checked the fuses on the kick panels.

With door open all instrument lights work. But when I switch from auto headlights to any other setting everything dims like it should.

All interior lights are working. Door lights, dome light, etc.

Right now I am leaning toward the dash light adjusting switch being bad, but I have not tested it. The door switch was replaced and is not the problem.

Is there one wiring set up for door open and another set up for door closed?

Any comments are welcomed.

Additional info: The lights are coming on. They are just very dim and will not increase in brightness. But upon starting the dash lights come up to full and then in about three seconds fade to very dim. The climate control lights are always dim and do not change when starting.

 

[Snowstorm]

Additional info: The lights are coming on. They are just very dim and will not increase in brightness. But upon starting the dash lights come up to full and then in about three seconds fade to very dim. The climate control lights are always dim and do not change when starting.

SOLVED sort of.

I was in the truck today and I noticed the lights were working as they should. But when I opened the door the brightneess did not change. But when I shut the door the lights flickered. Then I drove for a bit and noticed the lights going off and on.

Looks like a bad connection somewhere. So I will start searching.

Apparently the voltage is coming through, just sometimes not fully.

More to follow, but any comments about where to look are still welcome.

 

[UncleJakeNZ]

By 'dash lights ' do you mean the instrument binnacle backlights, all of the warning lights...or all of the above?

The door operated courtesy lights are switched to earth (rather than to positive) which may help your diagnostic efforts.

P.S. if you unplug the dashboard backlight dimmer switch completely the dash backlights will not work at all but the warning lights (seatbelts, highbeam etc.) will continue to operate.

If the plug behind the instrument binnacle is loose all sorts of odd things happen with the instruments (including oil pressure gauge)

 

[Snowstorm]

By 'dash lights ' do you mean the instrument binnacle backlights, all of the warning lights...or all of the above?

The door operated courtesy lights are switched to earth (rather than to positive) which may help your diagnostic efforts.

P.S. if you unplug the dashboard backlight dimmer switch completely the dash backlights will not work at all but the warning lights (seatbelts, highbeam etc.) will continue to operate.

If the plug behind the instrument binnacle is loose all sorts of odd things happen with the instruments (including oil pressure gauge)

The warning lights all work just like they should. The backlight is what I am talking about.

That is good info on the door switch grounding out. I replaced the switch with a known good one and nothing changed, but I think the door switch figures into this somehow. I am also going to check to see if the current is passing through the dimmer switch like it should. It could be is is flakey.

 

[Malleus]

By 'dash lights ' do you mean the instrument binnacle backlights, all of the warning lights...or all of the above?

The door operated courtesy lights are switched to earth (rather than to positive) which may help your diagnostic efforts.

P.S. if you unplug the dashboard backlight dimmer switch completely the dash backlights will not work at all but the warning lights (seatbelts, highbeam etc.) will continue to operate.

If the plug behind the instrument binnacle is loose all sorts of odd things happen with the instruments (including oil pressure gauge)

This is the way all Toyota circuits are designed. And why a bad ground is so hard to find...

 

[Snowstorm]

This is the way all Toyota circuits are designed. And why a bad ground is so hard to find...

I just checked the voltage at the fuse block. When the headlights are on there is power to the dash illumination lights.

I can sit in the car with the engine running and the door open and the lights are on. When I depress the door switch the lights go out. When the door is open the interior lights, like the dome light come on. When I close the door these lights go out just like they should.

This would be the dash illumination lights, the indication lights in the climate switches, and the digital readout of outdoor temp, climate control set temp and the clock.

Anyone know where the ground for the dash illumination lights is located? Could it be I need a new light switch?

 

[UncleJakeNZ]

One diagnostic step you could try is to partially eliminate the door courtesy switch wiring by removing fuse 6 from the kick panel.

That will stop your ceiling lights working by breaking the positive circuit to the dome lights, but it won't prove or disprove an earth fault. Try that and see what your dash backlights do.

You haven't mentioned if this is a new fault or the vehicle is new to you and came to you like this. If it's a new fault and you've recently fitted a new radio or some other electrical change then look there first. You may simply have a dodgy bulb somewhere in the lighting circuit.... but the change when any(?) door switch is activated has me stumped.

Toyota Land Cruiser 100 and Land Cruiser Amazon (1998-2007) Description of Fuses

Passenger Compartment LHD 1998-2003 2003-2007 UZJ100 RHD '98-'03: Turn Signal Flasher '98-'03: Fuse Box '03-'07: Fuse Box / Body ECU '98-'03: ABS ECU Tilt and Telescopic ECU Transponder Key Computer '98-'03: Wireless Door Lock ECU '98-'03: ECT ECU '98-'03: Suspension Control ECU Transponder Key

knigaproavto.ru

 

[Malleus]

Well, maybe here:

I'm assuming the grounds for the 2005 and 2006 are atleast similar, if not the same.

 

[UncleJakeNZ]

One more thought: The rear passenger doors and cargo door are a partially separate circuit to the front door courtesy light switches. Check to see what happens with the front doors closed but one of the three rear doors open.

Disclaimer: I have a 105 Series which is the poverty spec, so I'm only familiar with having two interior lights and not the 36,281 fancy lights you Lexus chaps enjoy. Ha!

 

[Snowstorm]

One more thought: The rear passenger doors and cargo door are a partially separate circuit to the front door courtesy light switches. Check to see what happens with the front doors closed but one of the three rear doors open.

Disclaimer: I have a 105 Series which is the poverty spec, so I'm only familiar with having two interior lights and not the 36,281 fancy lights you Lexus chaps enjoy. Ha!

This ground layout will be helpful. I have been considering the kick panel fuse but have not checket it yet. I will do so today.

I have had the truck for about six months. I have a 2000 LX I am going to sell but wanted to replace it before I did due to the roads around where I live.

I will also check the rear doors and see if they have the same effect.

I think I mentioned earlier that while working on this I slammed the door and the instrument lights lit up normally. Then they went out, blinked some more and then returned to being out. This leads me to suspect a bad ground.

One more thing that I don't know if it is normal or not: The under hood fuse for INST is not hot when the headlights are off but is hot when the headlights are on. And the instrument lights ARE lighting up with the door closed. They are just very dim and washed out by sunlight.

At night, with the headlights on, everything looks normal.

Is there a relay involved somewhere along the way?

 

[Snowstorm]

This ground layout will be helpful. I have been considering the kick panel fuse but have not checket it yet. I will do so today.

I have had the truck for about six months. I have a 2000 LX I am going to sell but wanted to replace it before I did due to the roads around where I live.

I will also check the rear doors and see if they have the same effect.

I think I mentioned earlier that while working on this I slammed the door and the instrument lights lit up normally. Then they went out, blinked some more and then returned to being out. This leads me to suspect a bad ground.

One more thing that I don't know if it is normal or not: The under hood fuse for INST is not hot when the headlights are off but is hot when the headlights are on. And the instrument lights ARE lighting up with the door closed. They are just very dim and washed out by sunlight.

At night, with the headlights on, everything looks normal.

Is there a relay involved somewhere along the way?

More info: I checked the other doors. If I open any door, including the rear hatch, the instrument lights come up to full bright.

Also I checked the lower row of pushbottons for the rear defrost and mirror heaters. They are lit up when pushed in just like normal. The indicatior lights for the climate control button is dimmed out like the dash illumination. As are the inside and outside temps and clock.

 

[UncleJakeNZ]

Pull out the tray the dash backlight dimmer is mounted into and check that the dimmer plug is firmly seated. It takes about 90 seconds and you don't need any tools.

Just pull the tray towards you when sitting in the driver's seat. It'll pop off. Have a search online for a video if you're uneasy just yanking on it

If the plug seating isn't the problem then completely unplug the dimmer switch and see if you have any dash backlights with doors opened or closed. You shouldn't.

Next - there's four screws holding on the binnacle itself, but you need to remove the upper shroud first. If the plug behind the binnacle is loose you can get strange symptoms

Another place to look is your body control module. It's just above fuse 6 that I mentioned a day or so ago.... but there's not much you can do with it if it's clean and corrosion free.

I suspect your dash backlights are finding their earth via the door courtesy light circuit - which they should not be, so your fault is most likely a poor earth to the dash somewhere. Hopefully just a loose plug.

 

[ramangain]

Or a dying dimmer switch

 

[Snowstorm]

Or a dying dimmer switch

I have not had the time to do any of this yet but I will tomorrow.

Additional info... The instrument lights are coming on during the daytime, but they are in the night time mode. The instrument light control is able to dim to zero and up to max but only in nighttime mode. The sky was overcast so I could see some light was displayed. And at night everything looks normal.

Also when starting the engine the instrument lights come up to full bright for about two seconds and then dim to night mode.

Turning the dimmer switch to 100% and then past to click the switch into full on will not change the light levels.

I am beginning to look towards the dimmer or the control module.

Next up: Dimmer switch test.

 

[ClassyJalopy]

Any luck with this?

 

[jerryb]

06-7 LX illumination file