By the switch, I presume you mean the set button at the end of the turn signal stalk. I'll rig it up so I can see if I'm getting 12 v while the car is in motion, but I've tested it for voltage half a dozen times with the car stationary in the drive way. Even with the car still running after a failed engagement while driving, it has always read battery voltage when the set switch is applied. It will be a good double check to make sure it is doing what it is supposed to while moving. Wiring/connector and grounds appear to be good. If the switch tests good, I may give the module a wack with a hammer and see if it starts to work.

 

What you want to do is make sure your familiar with the function when it engages properly then leave the meter hooked up until it won't engage, then see if the switch is at fault.

George

 

I pulled a circuit board from a junk yard cruise control module and it seems to have resolved the issue. The board was an updated part out of a later model, so maybe there were issues with earlier versions.

 

Glad you fixed up.