Printing it now will look over it while eating. Now fed! Do you know if 141 selector Is the top oneM84-86 or bottom one M87-88 ? What is on the stalk, Is it a 3position switch ON/OFF then spring loaded for Resume? & other switchspring loaded Speed Set? I suspect the bottom 141 Selector is the later model when not using the relay.

 

Looking at the circuit when the set speed switch is pressed there should be 12V at the relay pin 86 & when released 0V, worth checking first & also check P85 on the relay it should read 0 ohms to ground other than that there isnt mutch more to it realy.

 

It's funny I just realised something, I have a 1989 cruise control stalk which I believed was different from my 84, I took it outside and they are infact the same, I haven't checked to see if the part numbers are the same because that requires disassembling the dash.... very strange indeed, I might try plugging that in and see if that changes anything...

Ok the cruise control stalk has a hard physical off switch, you move it to the left into the on position, then there is a spring switch to the left for RESET and a spring switch to the right for TIP, at the end of the stalk is a spring button switch for SET

When I turn the cruise control ON the relay buzzes, when I depress the set button it stops chattering, reset and tip also provide a temporary (1sec) relief from the relay buzzing...

Could it be that my cruise control stalk has already been replaced but someone has spliced it in wrong, hence why its buzzing?

 

Ok who knows maybe i've found the problem in my manual it says

The original design cruise control switch is no longer available, the superceded switch kit requires replacing the harness connector to match the connector on the new switch, removing and discarding the cruise control relay and splicing the green wire of the relay connector (terminal 86) into the red/white wire in the relay connector (terminal 30)

 

If the stalk is the lower one M87-88, then its not suposed to have a relay. You could remove the relay & bridge the relay socket p86 to p30 which should go to p2 on the computer & then try the unit.

 

Ok awesome, I'll try that ASAP and get back to you, if it doesn't work then I am cmpletely stumped, I will also check the part number of the cruise stalk with the one in the manual to see if it is new or old style!

Thanks for your help Daryl!