Buick GL6 Trans Glitch: Dead Display + Gear Issues

Had the same symptoms on my 2017 Buick Envision with similar transmission behavior. The gear indicator on the digital display went completely dark, and the gear shift became noticeably stiff with grinding noises. The root cause was a faulty transmission control module affecting both the electronic display and physical shifting mechanism. This is a serious issue that requires immediate attention since it can lead to complete transmission failure if left unaddressed. In my case, the repair involved: Replacing the transmission control unit, Reprogramming the new module, Calibrating the gear position sensors, Testing the car dashboard communication system The job took about 2 days at the shop. Its important to note that driving with these symptoms risks damaging the transmission further. The electronic display failure is often the first warning sign of the control module starting to fail. Would strongly recommend getting it checked by a certified dealership since this requires specialized diagnostic equipment and proper programming of the new control unit. This isnt a typical independent shop repair due to the electronics involved.

Thanks for the detailed reply about the transmission control module. The symptoms you described match exactly what I experienced. I ended up getting it fixed at a shop that specializes in automotive electronics and transmission work. The car dashboard and electronic display are working perfectly now, and the gear shift is smooth again. Just wondering, do you remember roughly what the total repair cost was for your control module replacement? Also, has everything stayed working properly since the fix? Im asking because my gear shift occasionally still feels slightly different than before, though the digital display is functioning normally.

After getting the repairs done last month, everything has worked flawlessly on my Buick Envision. The instrument panel display shows the correct gear positions and the gear selector moves smoothly without any grinding. The total repair cost was 1000€ to replace and reprogram the defective control unit. The slight difference you feel in the gear shift could just be the normal break-in period for the new components. The control unit needs some time to fully adapt to your driving patterns. However, if the gear shift continues feeling off after a few weeks, its worth having the shop check the calibration again. The most important thing is that your digital display for gear selection is working properly now, thats usually the best indicator that the control unit replacement was successful. Keep monitoring how it feels, but based on my experience, once the electronic controls are properly fixed, the transmission should operate perfectly.

Thanks everyone for the advice. I took my car to a transmission specialist after reading these responses. They diagnosed a faulty transmission control module just like you mentioned. The instrument panel and gear indicator are both working normally now after they replaced and reprogrammed the unit. The total repair came to around 1200 Euro for parts and labor. They found the original control module had water damage which caused the electronic display and shifting problems. The mechanic showed me the corroded unit and explained how it affected both the digital systems and physical shifting. The car dashboard readouts are all working perfectly now and the shift knob moves smoothly between gears with no grinding. Such a relief to have it fixed properly. The shop also did a full transmission diagnostic scan to ensure there was no additional damage from driving it while faulty. This experience taught me to get transmission issues checked out right away when the gear indicator or shifting behavior starts acting up. Really glad I found a qualified shop that knew how to handle both the mechanical and electronic components.