Back after 7 years but got problems
Start with checking fuse 12 under the hood. Then check to see if you have power at the going to the multi function switch, cruise module and cruise interrupt switch. Check to see if you have power on the other side of the cruise interupt switch when the brake pedal is pressed. If the switch is bad or misadjusted it will be telling the module the brake pedal is being pressed all the time which will prevent the cruise from enabling.
After that you will need to check to see if you are getting voltage/resistance on each signal wire from the multi function switch at the base of the steering column. Following the flow of power from the wiring diagram we will be able to find out where the power stops.
After that you will need to check to see if you are getting voltage/resistance on each signal wire from the multi function switch at the base of the steering column. Following the flow of power from the wiring diagram we will be able to find out where the power stops.
As far as checking grounds, it looks like everything grounds through one module or another. If needed I can look for the wiring diagram for a particular module so we can check the grounds but I would start on the power side first.
