You might find that after being parked for approximately a day or slightly more, your 2021 through 2023 model year GMC Yukon has a low battery or even has no engine crank, indicating a fully dead battery. GM TechLink has now identified the reason for this battery issue and the fix qualified technicians can apply to remedy it.
As the first step toward remedying the problem, the technician will check to confirm that a 200 to 300 milliamp draw exists at all times in your GMC Yukon. This draw continues when the vehicle is shut off and gradually drains the battery, fully draining the charge in roughly a day.
An unplugged third-row power folding seat switch is the usual source of this ongoing 200 to 300 milliamp draw. The body control module or BCM of the GMC Yukon is unable to shut off if one of the power seat switches is unplugged and will instead stay in standby mode, which pulls a trickle of electricity out of the battery while the engine is not running.
Additional testing will confirm that your GMC Yukon’s third-row power-folding seat switches are unplugged and non-functional. These switches are to be found on the right-hand rear quarter panel in the SUV’s cargo area. If these switches do not operate at least one of the third-row power seats, then it’s likely one is unplugged from its wiring harness connector.
The technician can then check the switches for loose or unplugged connections to the harness. Reconnecting the connectors that link the switches to the harness should allow the body control module to shut down rather than remaining constantly in standby mode while the vehicle is parked and shut off. This will eliminate the power draw on the battery and stop the low or dead battery condition from occurring.