Oldsmobile/Buick Repair: 92 buick regal odometer, digital speedometer, speedometer cable

Question
i just bought this 92 buick regal. it has a mechanical odometer and a digital speedometer. the speedo works but the odometer does not, it is front wheel drive. i looked from the underside of the car and saw no speedometer cable. i have not looked inside the dash though. i did see a unit on the top right of the tranny that looked like a control module with several wires coming out of it. any idea if the odom and speedo are controled from the same sending unit/control module. i havnt yet had a chance to look for a repair manual that might say where sending units are located. any sugestions are appreciated. thanks

Answer
Hi Aaron,
The speed signal comes from a magnet sensor on the trans for both. It goes to a buffer in the dash, which splits it out.
In trucks, the mechanical odometer is operated by a little motor, and dirt seems to be the culprit that binds it up.
I don't know about cars, but suspect the same.
The fix on the trucks was to take the instrument cluster to a dealership parts department, and they would send it off.
Van