Gauge backlighting doesn't work

[azndeugene]

Hey guys,

So ever since I replaced the odo gears in my gauge the backlighting no longer works. All other lights in the gauge works, it's just the backlighting that has gone out. I just replaced the bulbs and that was not the problem. I checked fuse 23 as I saw in an older post that someone had a similar problem and that was their solution but that did not work for me. Has anyone had this issue before? It sucks driving at night without gauge lights

Thanks!

[DER E30]

Is it ALL the backlighting that doesn't work? Or is it just the speedo/whatever?
Did you leave a ground unconnected? Pin on the connecter came out?

[jimsbim]

Guage backlighting

Sorry I can't offer any solutions for you, rather I want to piggyback off your post.
About 25% of the time when I turn the lights on, all of my guage lights turn on as well. The other 75% of the time, only the left (speedo) side of my guages light up, UNTIL I give the right side a firm tap dead center on the tach, with my index finger. Then the right side lights up and stays on, with no flickers or other issues.
Like I said, the problem is intermittent. I never know if the right side back lights will come on or not, but the finger tap always does the trick.
I'm guessing it's a short somewhere, anyone have an idea where to start looking?
Thanks, Jim

[jlevie]

Sorry I can't offer any solutions for you, rather I want to piggyback off your post.
About 25% of the time when I turn the lights on, all of my guage lights turn on as well. The other 75% of the time, only the left (speedo) side of my guages light up, UNTIL I give the right side a firm tap dead center on the tach, with my index finger. Then the right side lights up and stays on, with no flickers or other issues.
Like I said, the problem is intermittent. I never know if the right side back lights will come on or not, but the finger tap always does the trick.
I'm guessing it's a short somewhere, anyone have an idea where to start looking?
Thanks, Jim

That sounds like a bad solder joint in the cluster.

[DER E30]

Sorry I can't offer any solutions for you, rather I want to piggyback off your post.
About 25% of the time when I turn the lights on, all of my guage lights turn on as well. The other 75% of the time, only the left (speedo) side of my guages light up, UNTIL I give the right side a firm tap dead center on the tach, with my index finger. Then the right side lights up and stays on, with no flickers or other issues.
Like I said, the problem is intermittent. I never know if the right side back lights will come on or not, but the finger tap always does the trick.
I'm guessing it's a short somewhere, anyone have an idea where to start looking?
Thanks, Jim

That sounds like my car about 10% of the time, or if it is cold out... Its always the speedo and a tap on the dash that fixes it.

[bmwman91]

Sort of similar issue here. I still have to smack the right side of the cluster housing once in a while to get the light and temp gauge to work. After pulling the cluster to check solder joints and stuff, the left side backlight stopped working unless I give it a good smack too. I didn't see any solder defects and even re-flowed most of the solder on the main cluster board since it was looking sort of pitted from the bulb contacts. The lighting on the left side is noticeably dimmer than that on the right side too.

[Gregs///M]

Replace fuse 23. Don't bother checking it, 20+ old fuses can cause intermittent problems.

I've also seen bulb contacts wear into the solder pads so deep that they make poor connections, try rotating the bulb a few degrees.

Also with any type of illumination problems, replace the bulbs where you are in there.

[azndeugene]

Ive replaced all the fuses earlier when I got the car in the summer when I had some other issues so I don't have to worry about age old fuses and the backlighting bulbs are brand new. I guess I'll have to try rotating them a few degrees to see if that works because even smacking the thing doesnt trigger the lighting :(

[Gregs///M]

If that does not work, might be worth looking inside the cluster. I've seen burnt up electrical traces for the illumination circuit. Or try smelling the cluster, if it smells burnt, it will require replacement or repair. I can also test and repair that circuit if you need.

[azndeugene]

If that does not work, might be worth looking inside the cluster. I've seen burnt up electrical traces for the illumination circuit. Or try smelling the cluster, if it smells burnt, it will require replacement or repair. I can also test and repair that circuit if you need.

How much do repairs normally run? I may have time to pull out the cluster again this weekend to check the board.

[jimsbim]

Thanks for the ideas guys. It's been a bit chilly up here in PA lately and I use the car as a DD. I'll try the fuse replacement now, but otherwise wait until warm weather to remove and inspect the cluster. The good news is that whenever I have a new passenger in the car, they all seem to get a big kick out of me smacking the tach to get it to light up!

[bmwman91]

..whenever I have a new passenger in the car, they all seem to get a big kick out of me smacking the tach to get it to light up!

You know you own an E30 when.....

[Gregs///M]

How much do repairs normally run? I may have time to pull out the cluster again this weekend to check the board.

Please send me a PM for a repair quote.