sorry for the delay............
Greetings...... “Hi, I’m Don (akaCustomer and I look forward to helping you!”
This sounds like a Communication issue with the Unit, BCM & the Communication Module
Use of GM Dealer Scan Tool is needed to Test & Program......
IF you had prior issues with Electrical, then be sure to take it back to the same Dealer that repaired, as they may have missed something or there could have been "electrolisis or corrosion" where the moisture contacted Electronic Components & they could be responsible.
There is a CAMPAIGN for replacing the Rear Head Rest DVD's
# *****: Customer Satisfaction - Dealer Installed Rear Seat Entertainment System - (Apr 23, 2015)
Subject: 14281 - Dealer Installed Rear Seat Entertainment SystemModels: 2014-2015 Chevrolet Silverado, Suburban, Tahoe 2014-2015 GMC Sierra, Yukon
*******THIS PROGRAM IS IN EFFECT UNTIL APRIL 30, 2017.*******
Be sure to mention that & see if your vehicle qualifies
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