GMC Hummer EV Steering Controls Go Dark, Common Fix

I experienced a very similar electrical fault with my 2021 GMC Sierra EV. As someone with some hands-on experience maintaining EVs, I can share that steering column issues like this are often related to the control module connections. The malfunction indicator in my case showed the same symptoms, complete failure of the steering wheel controls while basic steering remained functional. After vehicle diagnostics, the workshop found a damaged cable connection in the steering column that was causing intermittent electrical failures. The repair involved accessing the steering column wiring harness and replacing the faulty connection assembly. Total cost came to 95 Euro for parts and labor, which seems reasonable for this type of electrical repair. Before suggesting specific solutions, could you share: Have you noticed any warning lights on the dash? Did the issue start suddenly or develop gradually? Are there any other electrical systems showing problems? Have you recently had any other steering-related work done? This information would help determine if your issue matches the common control module problems these models can develop.

Thanks for the detailed response. Just had my 110874 KM service last week, and the issue started right after that. The steering control module failure happened suddenly during a regular drive. No warning lights appeared on the dash before or after the steering controls stopped working. All other electrical systems seem to be functioning normally. The error message on the display specifically mentions a sensor issue in the steering column, which makes me think the service work might have disturbed something. I havent had any other steering-related repairs done before this. Going to book it in at a workshop to check the control module connections. Hopefully its just a loose connection rather than needing a full steering controls replacement.

Having gone through this exact repair on my Sierra EV, I can say the timing after your service is a significant clue. When the technicians accessed areas near the steering column during service, they likely disturbed the wiring harness connection, this matches perfectly with my experience. The sensor issue message you are seeing strongly suggests a connection problem rather than a complete control module failure. In my case, the service technicians had accidentally dislodged a connector while performing routine maintenance, leading to similar steering controls malfunction. A few quick checks you can request at the workshop: Inspection of the steering column wiring harness connections, Control module connectivity test, Sensor signal validation, Error memory readout The repair should be relatively straightforward if its just a loose connection like mine was. My total repair time was under 2 hours. Even if they need to replace the entire connection assembly like they did with mine, you are looking at around 100 Euro for the complete fix. Make sure to mention the recent service when you take it in, this will help them target the most likely cause of the malfunction indicator right away.

Thanks everyone for the responses. Just wanted to update the thread with my repair outcome. Brought the vehicle to the workshop and turns out you were spot on about it being a loose connection in the steering column. The service technician found that the wiring harness near the steering controls had indeed been disturbed during my recent maintenance. The sensor issue was triggered by a partially disconnected plug that connects the steering wheel controls to the main system. Total repair cost was 85 Euro and took about an hour. They secured the connection properly and ran a full diagnostic to clear the malfunction indicator. All steering wheel controls are now working perfectly again. This might help others who experience similar steering control failures after routine maintenance. Make sure to have them check those connections first before assuming its a major electrical fault.