Replaced both bulbs in LCD backlight, still won't work

[Rannd]

Hi all,

I bought my 4Runner a few months ago and the left side of the LCD backlight hasn't worked where it shows the temperature, gas mileage, etc.

So I bought two brand new OEM bulbs... put them in there and now the left side works but the right side doesn't. Well this makes no sense... so then I took the right side bulb out and put one of the older bulbs that worked fine. Still doesn't work.

Is there maybe a issue with the circuit that I don't know about?

Thanks!

 

[ibanezjeepguy]

same issue with my father's 06 SE. very strange neither of us noticed it when driving off the lot last weekend. only the right side, left works fine. have yet to do any testing or troubleshooting. just responding to keep tabs on your OP.
I'll post back what I discover.

 

[mrpurplepenguin]

Do you have a multimeter? You can check voltage at the electrical contact pads, it should be 12V with the key on.

You can also check resistance of the bulbs themselves to make sure they're not burnt out. I'd be guessing at an exact value but it should be much less than 10k ohms.

Other than that, make sure the bulb leads are wrapped around the plastic base thing properly so they make good contact with the pads when it's all installed.

Maybe corrosion on the pads? If it's not working with a previously known good bulb, a poor electrical connection seems the most likely culprit.