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-   -   Odometer problem - burned resistor on circuit board (https://rennlist.com/forums/928-forum/1151505-odometer-problem-burned-resistor-on-circuit-board.html)

jas79 07-09-2019 05:46 PM

Odometer problem - burned resistor on circuit board
 
I've got a broken odometer on my 1986 Euro S. I replaced the odometer gear some years ago, and after that the odo worked fine. Now it died again. I guessed that iy was a gear issue again, and took it apart. No broken gear, and it counts fine when rotating the mecanism. There must be a electrical issue in the odometer. The speedometer works, so the impulse sender on the differential, the flexible circuit board, wireing etc must be OK. The problem must be in the odometer instrument. I found this excelent thread about problems i the instrument. Itīs only one problem with it. The pictures are missing. :(

https://rennlist.com/forums/928-foru...rs-intact.html

I soldered the step motor out of the board, and checked it according to the instructions. It works perfectly. I found one burned resistor on the circuit board. In #17-18 in the thread they talk about checking a resistor, that should be 22 ohms. Which one on the board is that? Anyone got the pics from that thread?

Anyone know the value on my burned resistor? I soldered it out of the board, and it is about 48 ohms now. I donīt know if it is the correct value, but it neeeds to be replaced. Maybe some other components too? It is the UAF2115 chip.

Any inputs and ideas are welcome!

/Mattias

https://cimg3.ibsrv.net/gimg/rennlis...c8ff984254.jpg

Majestic Moose 07-09-2019 06:26 PM

According to this thread it should be 33 ohm and it may have burned out due to a shorted capacitor.
https://rennlist.com/forums/928-foru...r-failure.html

jas79 07-10-2019 04:48 AM

Thanks for that link, very useful!

I will report back after replacing the resistor and capacitors.

/Mattias

Douglas Stout 07-12-2019 02:15 AM

I have the same burned resistor on my 85. I have no speedometer or odometer at the moment. It would be nice if someone sold just this circuit board, vs having to buy a complete speedometer assembly

Majestic Moose 07-12-2019 06:11 AM

I sent in my speedometer to Specialty Gauge and he replaced the board.

Cory Shepherd
Specialty Gauge
8110 Weatherwood Ct
Unit 202
Manassas, Va 20109
703 402 4008

Landseer 07-12-2019 12:30 PM

Maybe they will rework amp gauge too. Mine pegs out. Stan and I measured 12 volts. Must be something similar.

jas79 07-12-2019 06:59 PM

Report after repair:

I replaced the 33 ohm resistor, the 47 and 100uF capacitors, and now the instrument works perfectly!

I checked the removed components, the 47uF capacitor was broken but the 100uF was OK.

THANKS TO ALL HELPFUL RENNLISTERS - this forum is fantastic!!!

/Mattias


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