Hey guys I'm getting a code for the PCM P0564. I was driving on the highway with cruise on and it just turned off. The check engine light is not on and that is the only code there is. The cruise control will not turn on. I have tried all combinations of buttons and switches and know I am testing it correctly. I dont own a multi meter but am more than willing to get one to test switches. Just looking for some direction on where to start? Could it be the PCM relay? Or the brake switch? That would be the easy fix. I want to try easy stuff before buying a 100$ multifunction switch and taking apart the steering column.

 

Causes for this P0564 code may include:
Multi-function/Cruise control switch defective (i.e. stuck, broken, missing, etc.)
Wring problem (e.g. chafing on steering column/dash parts, water intrusion, corrosion etc.)
Connector malfunction (e.g. corroded pins, broken plastic tabs, swollen connector body, etc.)
Fluids/dirt/grime in cruise control button/switch causing abnormal mechanical operation ECM issue (e.g. water intrusion in computer body, internal short, internal overheating, etc.)

I would check ALL of the connectors leading form the Cruise "stalk" down the steering column and beyond first.
Then replace the stalk itself.
It can also be the brake switch (it shuts off the cruise when you hit the brake pedal)

 

That's pretty much exactly the information I'm looking for. I'll post what I find after I fix it.

 

it could also be the clockspring. this is a GM problem across the board. ive seen it on many silverados, acadias yukons etc etc.

 

My cruise control quit working on my 05H2, after checking bulbs, fuses, all working, i got under the dashboard, on the brake pedal there is a black box of some sort, there is a jack that plugs into it, i wiggles the the wiring harness that plugs into that box, and my cruise control started working again.
I guess i got lucky. Happens every now and again. Hope this helps you out.