my speedometer has been in a working when it wants to mode since i got the car in june. At times it would work sometimes it wouldn't i took the gauge cluster out too fix my tach which i did fix anyway i took the gauge cluster out and removed the motherboard on the speedometer it had carbon all over from where i dont know. i cleaned it up real good and put it back in and bam !!! i have a working tach and speedometer !!!!!!!!!!!


the dirty motherboard i was talking about






My fixed tach !!!! im so happy







this place rocks

 

How did you fix the tach?

 

I assume using this old sticky thread: https://www.thirdgen.org/forums/elec...meter-fix.html

 

Hey Lou, what's that black crud all over his board and where did it come from?

 

If I had to make an educated guess, I would say that is cap blew and spilled all over the board. The top does look bulgy from this angle (judging from the change in reflectivity). The electrolytic fluid is not an insulator, quite the opposite, so it probably added unexpected parasitic capacity to many places in the circuit, wreaking havoc on the readings.

But again, it's just a guess.

Lou

 

I assumed that also but would like to hear different if not.

 

It does look kinda puffy on top and the black stuff is right there at the base near a pin apparently. I've seen a bunch of popped caps in mother boards and none looked quite like that though. Never seen one bleed that black and it just looks strange how it gathered around those parts where they went thru the board. That looks kinda charred. Weird.

 

dont know what it was but once i cleaned it up it works like a charm

 

yep thats the one look at page 4 and above very easy to do