I was leafing through the back of my FSM and noticed that if you had an electro-cruise car, you could not get the speed alert function on the speedo, since the same knob was used to set your cruise speed. I further read that the cruise speedo would supply a varying voltage based on how far the needle was away from the set speed. After reading all this, I (apparently mistakenly) thought the cruise control speedometers had some sort of vehicle speed sensor in them. Since original cruise control parts are hard to come by, I gathered I could buy a cruise speedometer since it came with some sort of VSS, and if I ever wanted cruise, I would not have to stick magnets on my driveshaft. just adapt the signal from the speedo to an aftermaket cruise system. Fast forward a couple of months, and I notice a seller on eBay providing cruise parts for big cars: the switch, amplifier, and vacuum servo. I notice the speedo is never listed, and e-mail the seller. He didn't put it on eBay because the needle was buster. I twisted his arm and he sold me the needle-less speedo, as I have a parts car and a needle would not be hard to come by. I got the cruise speedo in, and compared it to the exploded view of a cruise speedo in the FSM. Everything seemed to be there. I then compared it to my non-cruise, speed alert speedo out of my parts car. This is where things get interesting. The cruise and non-cruise speedo I have seem to be identical except for one minor variation in wiring. If you look at the picture below, the factory speed alert speedo has a single blue wire coming from the connector, and it is bonded to the small white pickup wire on an insulated block. The small white wire goes to a pickup arm that makes a complete circuit with ground once you pass the speed alert set speed. The cruise speedo has two wires coming from the connector. One wire, that is in the un-used connector position in the non-cruise speedo, is bonded directly to ground. The other wire, the white wire, goes directly to the pickup wire, and is not bonded. About the only difference I see is the cruise speedo has a direct ground, instead of bonding through the dash screws that hold it in. I am missing the concept, or was I sold a non-cruise speedo? I know it is a long shot. Any help or links to websites would be appreciated. Thanks!
In case someone needs the same answer to the question... I found out there are no differences between cruise and non cruise speedos other than a cruise speedo gets a good ground, wheras the speed alert rely on the bolts that hold in the speedo to ground.
