I have a 2004 GMC 1500 with buttons on the steering wheel.  Last summer a soda exploded onto one of the button pairs and now it's sticky and if the truck is cold the buttons are unusable.  I tried waiting until the buttons were warm (sunlight, and dashlights on) and then spraying electronic contact cleaner back there, but the spray is below freezing when it comes out so immediately it locked everything up tight. 

I think the next step is to disassemble the steering wheel and manually clean back there.  Can anyone tell me how much of a process this is, and/or point me to directions?

I did find instructions for replacing a sw button on a 2005 GMC Yukon... are these right?  I wish it had pictures... these instructions assume a certain level of knowledge that I DO NOT have:

• Disable the supplemental inflatable restraint (SIR) system by removing the SIR fuse and disconnect the battery
• Remove the inflator module(air bag) using a blunt tool from the back side through the access holes move the retaining springs top and bottom aside to allow the module to move forward, repeat for the other side. (this can be tricky)
• Unplug the module and the horn switch
• Make an alignment mark in order to note the relationship of the steering wheel to the steering shaft.
• Remove the steering wheel nut.
• Remove the steering wheel using a puller
• Remove the shroud retaining screws from the back of the steering wheel.
• Remove the shroud from the steering wheel.
• position a blunt ended tool into the wire harness cavity (1) and apply moderate pressure in order to partially remove the steering wheel control switch from the steering wheel.
• Disconnect the steering wheel control switch electrical connector.
• Remove the steering wheel control switch from the steering wheel.
• Replace the button and reverse order to reassemble

Should have been drinking diet soda.... No sugar, No sticky!!

I would try the WD40 like Gard said and blow between the crevises with some compressed air. Maybe the WD40 will loosen things up and the compressedair will move it all down stream. I don't thing you want to be fooling around inside that steering column. Watch out for that air bag.... BOOM!

Hmm, vinegar is a good idea, as is blowing it out with compressed air.  I don't think I'd try WD40 unless I had no other choice... seems like it wouldn't be good for the vinyl... but maybe you already know it's ok.

It's possible that the electronic contact cleaner worked after all.  I just went out for lunch.  After the truck sat all morning in the sun, the button was completely free with no sticky sound or hesitation when I pushed it... both of which it used to have even once the button warmed up.  I wonder whether the extreme cold from the ECC makes the button freeze?  Testing that theory, I sprayed more ECC in there and it got stuck again, so I forced it a few times in both directions, trying to work the stuff into the mechanism.  I'll know for sure tomorrow morning after the truck has sat all night in the driveway.

Thanks guys, I'll post when I find out what works... I can't be the only one out there with this issue.