Per a recent report by GM TechLink, some units of the 2021 GMC Yukon and 2022 GMC Yukon may not open the rear window glass when using the Remote Keyless Entry transmitter (also known as the key fob) or when using the switch in the liftgate. The root cause of the issue may be the positioning of the rear wiper arm, which could be out of the fully locked parking position, preventing the rear glass from opening. To note, the rear wiper arm may be out of position, even if it looks as though it is not.
To address this issue, GM TechLink recommends that customers remove the rear wiper and activate the rear wiper motor, allowing the motor to fully cycle before turning it off. After doing this, reinstall the rear wiper arm and double check that it is in the full park position with the arm situated on the park ramp. This should then enable the rear glass to open. If the rear window glass still does not open after cycling the rear wiper motor, the rear wiper motor assembly may need to be replaced.
To note, a similar issue (and related fix) has also been identified for the 2021 through 2022 Chevy Tahoe and Chevy Suburban.
As a reminder, the 2021 GMC Yukon ushered in a brand-new fifth generation for the SUV, with the 2022 model year introducing just a few changes and updates. Specs include three engine options, starting with the naturally aspirated 5.3L V8 L84 gasoline engine, and followed by the naturally aspirated 6.2L V8 L87 gasoline engine and 3.0L I6 LM2 turbodiesel Duramax engine. The GMC Yukon rides on the GM T1 platform, with production taking place at the GM Arlington plant in Texas.