Ever since I got my 85 transam, the cruise control has never worked. Fitted a replacement cruise control switch / turn signal lever, checked the wiring under dash, the relay can be heard clicking.

Where do I go from here to determine the fault ?

Thanks for any help.

 

You need to check the servo to see if it is functioning. Disconnect the cable that runs from the servo to the throttle body. You have to build up vacuum so start the engine and run it for about a minute, then turn it off. With the ignition switch in RUN, and holding Cruise Switch in R/A, press and release the Set Switch. If it is functioning correctly the vacuum should hold the servo at wide open throttle position. If it is ok, I would then check the vacuum release valve at the brake pedal. Hope this helps.
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