Speedometer/odometer inop

E28 technical advice asked and given! Troubleshooting, modifications and more.
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AdamCContreras
Posts: 10
Joined: Jun 14, 2021 10:44 PM
Location: Santa Barbara
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Speedometer/odometer inop

Post by AdamCContreras »

Hey all! I'm new to this forum but not old Bimmers. I recently stumbled upon a couple E28's for $1,250. Both are pretty beat up, and both are automatic :( fixed up the 86 535i and sold it this weekend and now I'm going to use the money to fix up the 528e since it was the cleaner of the two. I am trying to figure out an issue with the speedo and odd not working in this car. The rest of the gauges work normal.

I started off by getting a wave form from the vehicle speed sensor in the diff and that came out good. Picks up with speed increasing and stays around 1.7v. I checked a wiring diagram and confirmed I'm getting the same signal at C2 pins 10 and 19 and that was good as well.

I checked for power and ground at the C1 connector where it stated on the diagram and I had good ground and voltage there.

I took the cluster out and fully disassembled and checked all the solder joints and everything looked fine. I don't know how to check the resistors since I'm not sure what they are supposed to be at. There were 2 3v batteries that both had 3.06v so those seemed fine. I checked continuity across the speedo/odo portion itself and the solders were intact allowing voltage and ground to go where it needed.

There was this goop coming out of a resistor looking thing next to a computer chip on the main board, it was a grey solid grease is what it looked like? I don't know?

I really just need advice on other things to check/replace or if you guys have a recommendation on where I can send this cluster to be inspected and rebuilt that would be awesome. I plan on using this forum and hopefully helping others once I gain more knowledge on this car. Thank you!
Last edited by AdamCContreras on Jun 16, 2021 11:51 PM, edited 1 time in total.
AdamCContreras
Posts: 10
Joined: Jun 14, 2021 10:44 PM
Location: Santa Barbara
Contact:

Re: Speedometer/odometer inop

Post by AdamCContreras »

So update. I ordered a cluster circuit board from Programa, much better deal than sending it out to anyone else. I got it all installed to the old cluster housing and now the speedometer works, Yay! However the odometer is still not working. Any idea on what to check for? I replaced all the odometer gears already so I'm a bit lost on this one.
MyE24
Posts: 94
Joined: Apr 16, 2021 10:43 AM
Location: California

Re: Speedometer/odometer inop

Post by MyE24 »

Where did you get the gears from?
Ju@n
Posts: 702
Joined: Apr 27, 2013 1:11 PM
Location: Uruguay

Re: Speedometer/odometer inop

Post by Ju@n »

Did you try manually moving the motor that turns the gears and confirm it is actually working?
AdamCContreras
Posts: 10
Joined: Jun 14, 2021 10:44 PM
Location: Santa Barbara
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Re: Speedometer/odometer inop

Post by AdamCContreras »

I got the gears from odometergears.com. It was the bundle of 3 gears. Super easy replacement. When I turn the little small one forward or backward the odometer and trip meter turn. What motor should I turn? The little black one on the opposite side with the rod to the little gear? It’s under a clear plastic plate with 2 screws right? I’ll have to pull the cluster again and check.
milarsky
Posts: 515
Joined: Jan 26, 2013 11:19 AM
Location: NYC

Re: Speedometer/odometer inop

Post by milarsky »

Long shot here, but have you checked the bullet fuses marked "tach, odo, etc"
AdamCContreras
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Joined: Jun 14, 2021 10:44 PM
Location: Santa Barbara
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Re: Speedometer/odometer inop

Post by AdamCContreras »

Yes, if you mean the ones in the engine bay, driver's side, I checked all of those and they were good. I checked for power on the bottom of the terminals that hold them to make sure there was not a fuse contact issue within the holder. If there are other fuses please let me know. I haven't had time to pull the cluster again for inspection but I'm thinking it's something with in the speedo/odo portion of the cluster that was not replaced.
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