If my lights are on my cruise control will not work. If the lights are off the cruise control will work. If I use my left blinker the cruise control shuts off. But not the right, Also the engine will jump like 200-400rpm when ever I use lights or left blinker. I know it sounds like I'm playing but I'm not. It's very weird. I can figure it out! Anyone have any idea?

 

I would start with the basics like the battery connection, sounds strange however when the lights turn on thats a big volage drop and might kick the cuise control off because it cannot mantain volatage. other then that you might want to start looking for ground faults.

 

Anyone have a ground diagram for the cruise control? Well does anyone have a location for all the grounds?

 

get a Chilton guide that has plenty of diagrams, im not sure if there's a diagram thats going to show locations of the wires. your probably going to chase some wiring. however thinking about it more. most of that wiring is in the column or close to it id check under the dash and around the column for chaffed wiring around moving parts.

 

Thanks guys really love the help everytime I post something!! Will do a follow up by Monday!

 

cool good luck! hope you find the problem.

 

Your turn signal switch brushes (and horn sw) are right in the middle of the on-off circuit controlling the cruise control. Since they're "mechanical" and heavily used I'd start looking for a short there ------------do you have a Power Probe test set??

 

Well still no luck. Truck is also shifting erratically when lights are on.

 

Ha found it it was the led brake lights. That have been causing all these issues. Put some regular 3157 and everything is good now!

 

Yep, some of the "ebay" LEDs are x-wired internally, some have poorly spec'd load resistors and upon inspection of the wiring diagram for your application, the stop light bulb is in the circuit with the stop light switch which also feeds the cruise control, transmission, and anti-lock.