Cruise control

I have just bought a '92 F150 and the cruise control is not working. Is there a common problem area with the system, where should I start looking ? At the moment I do not have a workshop manual, is there one that would have a schematic of the cruise control system ? Any help would be most welcome.

Thanks.

Call the dealer first if yours is under the recall.There is a recall on this and it is no charge on the fix

Check the fuse for the AC and see about that recall.

I know a guy that took his 1993 in for cruise control problem to the dealer and they fixed it under the recall on the spot.