Illumination Failed On Temperature Control

[IronIron]

Hi, I have a 2010 IQ1 and a couple of days ago the illumination behind the temperature control knob stopped working (the dial that you rotate to control hot/cold and has the rear heater element button in the centre). Surprisingly the loss of this illumination is actually quite annoying as I do both my commutes in the dark and cant tell what the dial is set to anymore.

The temperature control itself still works and I checked all the other dash buttons and lights and all seem OK, so it's just this one. So I’m thinking that it isn’t a fuse?

I’ve had a look at the removing your dash sticky, which I’m hesitant to attempt it to be honest. I’m wondering if anyone has had this problem before and can tell me if there is even any point removing the dash myself to try to fix this – is there actually a replaceable part behind there like a bulb?

[tarquin]

Hi there. I have removed this unit many times. One of my modifications i have done for people is to change the dashboard LED's to blue like mine. The version that has manual control heating as opposed to climate control have filliment bulbs in the centre of the knobs You have to take the "V" shaped unit out and look behind it to behind where the mechanical cables come away from the controls. There are small flat blade screw driver slots that turn and the bulb can be removed for testing. Not sere if Toyota sell them as they are unusual. They also have a small rubber cover over them. If on the other hand its round the outside of the dial they are LED's for illumination then it may be a fuse or worse

David

[IronIron]

Many thanks for the advice, hopefully it is a bulb because i suck at soldering :)

[tarquin]

Hi where abouts in the country do you live

David

[IronIron]

North London. Haven't had a proper go at this yet: I've yanked the top part of the centre console off (to check it does come off that easy), but quickly put it back because my other half was horrified. I'm waiting for a sunny day to have a real go at it so I can see what I'm doing.

[IronIron]

Sunny day today, so gave it a go:

It was quite easy to get down to the actual units, but then I had to disassemble them to get to the bulbs. The bulbs are LEDs, but they are replaceable ones. I switched the one that wasn't working with a working one in another control and it worked, so seems it was just a dead LED.

After I had already worked out the disassembly for myself, I was searching online for the bulb size and found this great guide for changing the bulbs. It isn't for the IQ, but the units look the same as the one in the IQ (to my untrained eye anyway). After the panels are off the process is almost the identical to what I did.

http://www.carreviewsncare.com/do-it-yourself-replace-toyota-vios-air-conditioner-panel-bulbs/

The bulbs appear to be T4.2 bulbs and you can get them off eBay (in different colours if you want)

[tarquin]

Excellent work. On tbe cars i modified the dash to blue i simply took the greeny/amber cover off the bulb to make them white so they were in keeping with blue.

David

[IronIron]

Has anyone managed to dissemble the hazard light button? I got it away from the dash no problem, but when I tried to separate the front from the back of the unit (so I could get at the insides) the plastic started to crack so I stopped. Is there a trick to opening it up and does it have T4.2 bulb in there or a different size?

NB: I've replaced the bulbs on the three central console dials with white ones and wanted to change the hazard bulb to match.

[tarquin]

The hazard bulb is already white/clear. Its only the red plastic that makes it illuminate red

David

[IronIron]

I think there must be 2 bulbs in the hazard button as is the case with the air con and rear heater dials? There is one bulb to light up when you press the button (e.g. rear heater) to show it is on and another back-light bulb which only comes on when you turn on your headlights. It is the back-light bulb that I am interested in changing, it gives off a kind of amber glow on the standard hazard button. I've changed all the others in the centre console to white so now it looks a bit odd.

It did really look like the plastic was going to snap as I tried to open it, so not keen on experimenting myself on how to open it up. Hopefully someone has done it before?

[tarquin]

My understanding is and certainly in the climate control version that it comes on when the lights come on and is illuminated red with a white lamp. The built in actuating switch only operates the hazard flashers. The actuating switch is independant of the ignition and operates the hazard lights without the ignition on. The trisngle only illuminates with the one lamp when the lights are turned on

David