i checked the brown wire at the brake pedal switch (it is a 700r4). and there wasnt 12volts what do u suggest? also for the life of me i could not find the module. i looked for an hour. i found a yellow box next to the ecm i swapped it out and nothing changed.i took the passen. kikpanel off and there is nothing under it.if possible could u b real specific to where it is? also how would i know if the switch in the collum is bad thanks for your incredible patience and info ed

 

Maybe it is the yellow module, but usually the VATS (vehicle anti theft system) module is yellow & VATS wasn't used until '90. Here are the wire colors connected to the cruise module:

Brown: +12 volts with ign & cruise switches on & brake not depressed.

Gray: +12 volts with ign & cruise switches on.

Dk blue: +12 volts with ign & cruise switches on & set switch pressed.

Gray/blk: +12 volts with ign & cruise switches on & resume switch pressed.

Brown: From vehicle speed sensor - 2000 pulses per mile.

Black: Ground.

Lt. green: To servo.

Dk. blue/wht: To servo.

Lt. blue/blk: To servo.

Tan: To servo.

Check all of the wires that have +12 volts to them for power & the others for continuity.

Tim

 

tim, my 89 definately has vats... so do u still know where the cruise module is assuming that the yellow box next to the ecm is for the vats system? also how would u troubleshoot to see if the switch is bad? how does the current flow. is it from the battery then to the fuse (guages) then the switch then the module then to the servo? in what order does the current flow? i am just trying to pinpoint where the current stops because i have no 12v at the switches on the brake pedal. but i have 12v at the fuse for the guages and the fuse is good from there on i cant find where to look next for the 12v. thanx again i really do appreciate it ed

 

Looks like I need to do some research on the exact year VATS was deployed in F-bodies......The cruise module is near the VATS module - probably toward the center console - you may have to pull top of the dash off & view it from the top - then you may have to pull the dash assembly back to remove the module. Check for power starting at the source - the fuse & then trace it from there - if it does not make it through the brake switch, then that is a problem.

Tim

 

If the yellow box you found had a purple, yellow, two brown, red, black, and a pink w/black tracer you found the vehicle speed sensor buffer, the crusie control module should been on the passenger side behind the dash about in the center or a little right of center.