Corolla 2001: Climate Control Knobs

I have a 2001 Corolla CE with climate control knobs that don’t light up (the buttons between them do because the middle light works, just not the other two).

First, I unscrewed and pulled out the climate control box and in the process of doing so, the left knobs lit up because (if my new assumption is correct) the problem isn’t the bulbs (which aren’t burnt) but rather the wiring, which I must have unintentionally reconnected as I pulled the box outward. Unfortunately, the knobs stopped lighting up after a little more movement and I can’t replicate the condition that caused them to light up.

My current plan is to remove the climate control box from the wiring and cables to see if there’s something wrong with the contacts or the wiring itself, but I don’t know how to disconnect the cables and I’m not sure how to test the wires even if I find something wrong.

Any ideas as to what I should do at this point?

(FYI: I also removed the console frame and the lower parts to get a better look at the bottom of the box and its wiring as you can see in the picture)

The problem could still be in the control unit and moving it around made/broke the connection. I’ve also seen bulbs with broken filaments that will sometimes work again if you jar them enough for the broken end to make contact again.

Usually the bulbs are replaceable. (on most cars, not sure about Toyota) I’d get the head unit out and look at the bulbs first before worrying that the wiring may have a problem.

There are small bulbs back there. They should be replaceable. My Toyota has electronic climate control, so the controls are in a sealed module. Fortunately, all the backlights still work. However, I have courtesy lights for other simple switch controls that I have had to replace.

Oblivion, thanks for explaining the broken filament incident! You were both right and I replaced the bulbs successfully with your help!