After tearing down my dash, now my instrument panel is acting weird.

I just finished up replacing my heater core (terrible job), and I put my dash all back together. Now when I drive my jetta, the instrument panel doesn't show any gauge readings or dummy lights.

The weird thing is, the odometer, blinker lights, instrument lights all work.

However, my temp gauge, speedo, tach, and fuel gauge does not work.

I checked my connections thrice to make sure the plug was fine. It looks ok to me.

In the last few years, I noticed that when I started my car after a long vacation, my gauges wouldn't work for a few minutes, but they'd always fire up after a bit of driving. I ran this for almost an hour, and the gauges never fired up. It appears that while I had my instrument cluster sitting in the garage, it might have permanently damaged the cluster.

Does anyone have any ideas on how to get this working?

sounds like a bad ground

Most likely bad cluster. I picked up a cheap spare out of a gasser that I installed to verify it wasn't anything with the car. Ran with that while I got my cluster repaired at a gauge shop.

then its clearly bad solder points within the cluster, easy to fix, if you have a solder gun and some time

Mongler98 said:

then its clearly bad solder points within the cluster, easy to fix, if you have a solder gun and some time

Click to expand...

I got a gun and I can solder pretty ok. Is there a write-up on this forum or on the net that shows what to do?

I ordered a spare TDI cluster from ebay last night. I'll wait to install the spare cluster before tearing down the bad cluster.

Ran with that while I got my cluster repaired at a gauge shop.

Click to expand...

Which shop did you use?

I used a local shop, which was a bad experience. It's gone relocated to AZ.

Derek White at Chubs Auto is the man to send your cluster to on the board. He can fix pretty much anything and has converted or repaired 6 or 7 for me over the years. I just got 2 more back from him not long ago.

Personally I think it's a stretch but part of he cluster functions are grounded out under the hood near the 'orb of death' connector. The bracket that holds the orb and mounts to the cyl head coolant flange on the side also has a couple ground wires attached to it. When I lost some cluster functions it was due to corroded ground out there.

Since you've recently dismantled your dashboard I doubt that this is it but it's worth checking.

I would personally be concerned that something got pinched / cut when you were reinstalling the dash etc.

Good luck

Steve

Uh Oh. Burnt Smell

Now something bad happened. I was driving, and my heater fan didn't work on low or med. That usually means my resistor is shot. talk about bad timing, after taking that whole dash apart.

I drove around town with the fan on high. Then when I parked, I turned it down to med, and it worked. Also, it worked on low. Odd.

I did some shopping and returned to my car. Kind of a elec burn smell in the car. My fan still works on all settings, but the dash smells burned. I couldn't detect any smoke, but there is a smell to the thing.

I'm thinking the ground is bad, but where? It probably has something to do with the wiring to/from the blower motor/resistor. What is the ground for these components?

genscripter said:

Now something bad happened. I was driving, and my heater fan didn't work on low or med. That usually means my resistor is shot. talk about bad timing, after taking that whole dash apart.

I drove around town with the fan on high. Then when I parked, I turned it down to med, and it worked. Also, it worked on low. Odd.

I did some shopping and returned to my car. Kind of a elec burn smell in the car. My fan still works on all settings, but the dash smells burned. I couldn't detect any smoke, but there is a smell to the thing.

I'm thinking the ground is bad, but where? It probably has something to do with the wiring to/from the blower motor/resistor. What is the ground for these components?

Click to expand...

I believe that all this is pointing back to the reassembly and suggesting that the wiring has been compromised somewhere and in some way.

I would start by dismantling the center section of the dash, the lower glove box (where blower wiring is) and pull the cluster out too and I would look for melted wires and figure out whether I routed some wires poorly.

As for the grounds the blower motor IIRC is grounded to the adjacent door pillar area to the right of the blower. The other ground cluster is on the left near the driver behind the knee bolster and metal.

It's unlikely that these are isolated incidents.

Steve

I tore down the right side of the dash and nothing looks burned. I ran the blower motor again, and nothing felt hot.

I'll look at the center console wiring tomorrow. I'll check the ground next to the blower motor now. I cleaned up the engine ground while I was inspecting the engine bay. Do you know where the ground on the cylinder head is?

I took the jetta for a spin after cleaning the main engine ground cable connection. Now the instrument cluster works. Weird

I put in the new radio, looked for more issues and couldn't find anything. Then I noticed that my HVAC dials didn't illuminate. I think that must have been the burnt smell. The bulb burned out. IDK. I'll tear it down and check it out. TBH, I can't remember if the dial face-plate illuminated or not. Not really something you notice until it's gone.

Interior grounds at the engine are at the block bracket mounted to the flange on the side of the cylinder head, just below the round engine connector that we fondly call the orb of death. There are two wires there that can affect interior electrics. Those grounds need to be cleaned, one of the two does affect cluster operation.


Steve

I cleaned up the grounds on the interior of the car. They looked ok to me. While I was at it, I added another ground cable to the dash metal support, just in case that had a shabby ground under all this mess.

I checked all the wiring on the HVAC climate control. Nothing looked burned or melted.

It rained last night, and not sure that matters, but this morning, my instrument cluster stopped working again.

I ordered a new instrument cluster on ebay, and coincidentally it arrived today. I installed it and all the lights work now. I think my cluster is bad, because I read a bunch on the wring on these clusters, and it appears to be something internal.

I'll clean up the orb of death, carefully. I have a california car, so for the most part, none of my grounds appear to have any corrosion. When I clean them up, I make sure to apply dipole grease.

While I was fiddling around, I found the bulb that burned out. Here's a picture. Do you know where to find a replacement? It has a serial number, but it's so small and rubbed away, that I can't decipher it. Something like this: OS 12 / X2 76

I don't know why this photo isn't loading. I'll try again.

Is this my browser not showing the picture? Can you guys see this?

I think i found the light bulb on Amazon. Does anyone know if this is the correct bulb? https://www.amazon.com/SYLVANIA-2721-Miniature-Contains-Bulbs/dp/B00318NUCI

I bought some at oreilly at one time I think, can't remember the specs though.


Steve

I bought a bunch from NAPA but I'll have to look up the number.

The HVAC backlight and the B4 3rd brake light bulbs are the same. Here is a spec comparison:
https://forums.tdiclub.com/showthread.php?p=5014939#post5014939

I usually search T10 and come up with a compatible LED.

-Todd

T10’s and T15’s are usually the twist-in lights that are in a socket, but yeah those lamps are usually the right size without the socket.

They’re compatible, if running LEDs. I’m currently using them, in the HVAC panel and the cluster, using modded Subaru bases.

-Todd

I ordered a set of incandescent style bulbs. they arrived today, but I haven't had time to replace them.

I drove the jetta for a long drive this weekend, and for the most part, the new cluster and all the electronics is working well. However, randomly, my low and med blower motor settings will not work or blow very slow. My high and very-high works fine.

I'm thinking my resistor is acting up, but maybe I have another ground that isn't connecting well. All my grounds are clean though.... hard to say what is going on. I'm tempted to replace the resistor, but if I have a bad connection somewhere, it'll probably still act up. Not sure where else to look. I'll keep chasing these gremlins.