Gauge Cluster DIY Repair

[Regin8r]

I’m writing up this DIY for anyone that has problems with any of the gauges on their gauge cluster. In my case, I was installing the Bimmian Gauge Face which caused my speedometer to not work properly(binding at 20kph). But I also had problems with this cluster a while back with my coolant gauge always in the red. The dealership diagnosed it as a problem with the gauge cluster and said I would require a new cluster to the tune of about $1k. I declined at that time and hedged that if I kept up with my thermostat, water pump and coolant changes, I should not break down because of that.

Anyhow, here’s my gauge cluster story…

Original cluster:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_000.jpg

Removed:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_001.jpg

The face plate:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_003.jpg

Original cluster:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_005.jpg

Completed:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_006.jpg

[Regin8r]

It was all well and good until I tried driving and saw that my speedometer was binding. I tried taking off the plastic shield and driving carefully coaxing the speedometer needle up and found that if I forced it past 20kph, it would work normally until I decelerated below 20kph, and then eventually it just stick at 20kph.

Through my sleuthing and detective work, I figured the problem was actually caused during Step 6. When trying to zero back the gauges, the speedometer gauge being the most delicate, had one of the fine gears behind the needle damaged. I'm not very used to macro photography, so I did what I could.

I opened up the gauge cluster again:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_011.jpg

Flipped it over:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_007.jpg

Selected the speedometer needle module:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_008.jpg

With a pair of precision screwdrivers, I pried open the back of the module:
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_009.jpg

When you look closely at the black gear, I saw that I had a damaged prong in the "black" gear which I unsuccessfully tried to capture on camera, but I circled it in red.
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_010.jpg

Since my coolant temperature gauge had been busted at the time, I opened that up and swapped the "black" gear. Assembled everything back together and slowly zeroed the gauges. At this point, I did notice the speedometer needle had noticeably more resistance than the other gauges.

This would pose a problem because when I drove, now the speedometer was stuck at "0".

Great (sarcasm)! Off comes the cover again, and I nudge the speedometer along and it does appear to work if I give it the nudge, but not on its own. Back to the drawing board.

[Regin8r]

So I take apart the thing again and examine the other gears again. The "black" gear is fine, but what about the "white" gear?

http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_016.jpg

Upon closer inspection, I see that there are 2 more potential problem areas that you'll have to check.
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_015.jpg

In red circle, you'll see that my constant nudging has stripe 1/2 the teeth off the white gear. And the binding is caused by the 2 green circled nubs being compressed down (caused by the prying off of the needles of step 5 in the instructions). The nubs allow the gear to "float" above the base of the module. If it's not "floating", it's fully depressed and the resistance is increased dramatically.

So I swapped the coolant gauge "white" gear and the speedometer "white" gear, and that fixed my higher resistance problem, but not the fact that I've stripped the teeth. The coolant "white" gear also had some damaged teeth and at this point, I realized I just need to replace those "white" gears and in theory, both should work.

I ended up buying a used cluster from the US from a 325i which I assumed is the same internally. They are available for about $150-200.

At this point, I used my lessons learned to install the gauge face on my wife's 330i. It worked successfully, without a snitch. That being said, the nerves got rattled a bit when I saw that the modules on the back of my wife's 330i had totally different model numbers. Her cluster was made by Bosch and mine was made by Motometer.

Great (more sarcasm)! So the cluster arrives, and I open it up and it’s Bosch of course! To my surprise, when I open the back, I find they use the same modules:

http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_012.jpg

Original module (X15-589):
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_013.jpg

Replacement (X15-589):
http://i24.photobucket.com/albums/c15/Regin8r/2008%20Automotive/2008_gauge_face_014.jpg

There must be something about that speedometer gear that's inherently weaker than the other gauges. When I pulled out the needle of the new cluster, I found that I compressed those tiny nubs on the new "white" gear. Luckily all of the modules are the same and I now I have a bank of 5 to play with. I take the one from the fuel gauge for my original coolant gauge and the fuel consumption on for the speedometer. Now the resistance for all gauges are the same, I assemble everything, put it in the car, and voila!

Everything works again!

Just one thing, you have to be careful not to damage the gears when putting the back part onto the needle module.

[zorin]

Very interesting reading - thanks.

[DaveL]

Thanks for posting.

Was this one of those tasks that you reach a point and say, "wish I hadn't done that!"