i have a 1983 633 csi and can not figure out why my spedo does not work... ive tested the speed sensor in the axel and it is good... ive also tested the spedo its self and was good... i have no clue as to what is next to check... and also what is the little key pad deal below the radio? thanks in advance for the help... kindrik

check out the bigcoupe.com forums, as well, there is alot of usefull info over there...i was having the same problem for the most part....i just ended up replacing my speedometer with a used one that i picked up on ebay..problem solved....until that one breaks.....or you could find a local speedometer shop and have them take a look at it....i dont remember the other possible causes off the top of my head but run over to bigcoupe.com whislt your waiting for more helpfull replies here other than mine...

ohh also check the main circut board for corrosion as well as the pins and terminals that the speedometer uses to connect to the board inside the cluster....if there is corrosion on the pins and or terminals you can generally get it cleaned off with a terminal cleaning tool or something of that nature....ive heard of this happening and causeing the speedometer not to function..

thanks man... i checked for corosion and it was all clean... ill check out that site... thanks... kindrik

Did it act up before it stopped? Was the odometer working as well? The odometer gears are notorious for breaking and they can keep the unit from working properly if they get lodged in the wrong area. It could be a simple fix.

i have a 1983 633 csi and can not figure out why my spedo does not work... ive tested the speed sensor in the axel and it is good... ive also tested the spedo its self and was good... i have no clue as to what is next to check... and also what is the little key pad deal below the radio? thanks in advance for the help... kindrik

How did you test the speed sensor? I've had the same issue on one of my E24 and I needed to take out the sensor and clean it. AFter that everything was working again.
Wolf

I just fixed a dead speedo in my '84 633csi. A new SIL (service indicator light) board brought it back to life. Found it on eBay for $75. There seem to be two types available -- a rebuilt board with the soldered-in NiCad batteries like the original and a new aftermarket type that uses capacitors in place of the NiCads. I bought the capacitor type and it works great.

Screwy gauges are a common symptom of the SIL board dying. If you also have dead or malfunctioning service indicator lights then the odds are even higher that that's the problem.

Whoops! That should be the SI board, not the SIL board. And it stands for "service interval" not "service indicator".