Service Driver Assist System

Just got mine fixed on a 2023 3.0L Duramax Silverado 1500 LTZ. Turned out to be a motor under my driver seat. The alert setting was set to “vibrate”, but it would never vibrate. It made an audible noise, which means there’s something wrong with the system. One dealership told me two months “your truck just needed a dealership update, and that fixed the issue”. The error reappeared, and I took it to a different dealership to find the issue. Below are the details of what the dealership found/did:

“Concern: Customer states service driver assist message randomly pops up. Cause: Verified customers concern. Service message illuminated. During diagnostics, found DTC B1388 stored in vehicle due to left rear haptic motor failure. Correction: Replaced driver seat leaft rear haptic motor. After repair, verified all ok.”