Hi,
I would like to share my recent (successful) experience fixing cruise control on my 1992 900. It started malfunctioning several years ago, and ultimately stopped working at all. I fixed it by re-soldering the contacts on the circuit board, but it broke again after about a week. It is my understanding that the circuit boards in the 41 08 643 cruise control units (used in >=1992 c900s) and their counterparts in the >=1992 Saab 9000s (41 08 650 I think) fail quite often.
I saw a post by Jeff on the saabnet.com Saab 9000 bulletin board that addresses this problem. He successfully used the 95 26 757 (from the pre-1992 Saab 9000) or its counterpart from the pre-1992 c900 to substitute for the faulty post-1992 unit. The central problem with this scheme is the different wiring connectors. He received this wiring diagram from Ville V A Hinkkanen in Finland, which outlines how to connect the pre-1992 cruise control module to a post-1992 car (colors may vary a little, but pin numbers are right):
1 (brown) -> 10 (red) 12 V, if ignition 2 (red-white) -> 3 (red-white) SET => 12 V 3 (black) -> 5 (red-white) brake & clutch pedal 4 (grey) -> 7 (grey) vacuum pump 5 (blue) -> 11 (blue) speed signal 6 (yellow) -> 4 (yellow) RESUME => 12 v 7 (orange) -> 6 (orange) vacuum pump 8 (black) -> 8 (black) ground 9 (red) -> 1 (red) & 9 (white) 12 V, if the cruise is onI took his suggestion and made an adapter cable by connecting the wiring harness that goes with a 95 26 757 (harvested from a 1990 Saab 9000) to the male connector removed from a broken 41 08 643 unit. I used this to connect the
95 26 757 cruise module to my 1992 c900, and it worked perfectly. Plus, the "accel" feature works by pressing the "set" key, which is a feature that hadn't worked since the car was new.I think this should work for connecting cars with broken cruise modules 41 08
643 or 41 08 650 to replacement modules 95 26 757, 85 87 016, or 95 60 905.I am very happy with how this turned out, and I hope other people with broken cruise control in post-1992 900s and 9000s will find this post helpful. Special thanks to Jeff from the Saabnet 9000 BB, and the guy from Finland.
John