VW Lupo Auto Trans Failure: Grinding & Display Dead

Faced similar issues with my 2008 VW Polo TDI. The instrument panel symptoms you describe match exactly what happened, gear position display malfunction and gear selector problems. The control unit ended up being the root cause. Our symptoms started with intermittent gear display issues on the car dashboard, then progressed to complete gear shift failures. The transmission control module was diagnosed as faulty, causing communication errors between the gear selector and transmission. This required replacing the entire control unit and reprogramming the new module to sync with the car systems. Not a simple sensor problem, it was a major repair that took several days to complete due to parts ordering and programming requirements. In your Lupo case, the grinding noise suggests the issue may have already progressed beyond just electrical problems. Continuing to drive with these symptoms risks causing permanent transmission damage. Would strongly recommend getting it diagnosed at a workshop specializing in VW automatic transmissions. The control unit failure is a known issue in these transmissions. While expensive to fix, addressing it early prevents more costly transmission repairs later. Make sure any replacement unit is properly coded to your specific transmission type.

Thanks for the detailed response about the control unit. Those transmission problems sound identical to what I experienced. Since you went through this repair, do you remember roughly how much the control module replacement ended up costing? Just trying to budget properly. Also, has your electronic display and gear shift been working reliably since the fix, or have you noticed any other sensor problems popping up? My gear indicator is still acting up intermittently and I want to make sure I fix everything in one go if possible.

Following up on my earlier post, I had the repair done last month and the total cost came to 1000€ for the control unit replacement and programming. The automotive electronics specialist completely resolved the gear shift indicator display fault I mentioned before. Since the repair, the instrument panel works flawlessly and shows correct gear positions at all times. The shift knob now moves smoothly between gears with no resistance or grinding, exactly how it should function. After they replaced the affected control unit that was defective, all the electronic transmission issues disappeared completely. The digital display is now consistently accurate and responsive. Based on my experience, if your symptoms match what I described, investing in the control unit repair will likely solve both the gear position indicator and shifting problems at once. Just make sure the shop fully tests the transmission communication system after installation to confirm everything is properly synced. Going to a specialized workshop made a huge difference in getting it fixed right the first time. The diagnostic equipment they used identified the exact control module failure point pretty quickly.

Thanks for the insights everyone. I finally got the car checked at a transmission specialist after seeing these responses. Like many suggested, it turned out to be the control unit causing problems with the automotive electronics. Ended up paying 1200€ for the complete fix, slightly more than expected but worth it. The mechanic showed me the old control module which was totally fried. The car dashboard now displays gears correctly and the gear shift is back to normal with no grinding noises. The specialist also ran a full sensor problem diagnostic check to make sure there were no other underlying issues. Really glad I found this forum and got proper advice instead of going back to my old mechanic who probably would have just changed the transmission fluid and called it fixed. The electronic display is working perfectly now and the transmission shifts smoother than it has in years. Should have done this repair months ago instead of trying to live with the problem. Definitely recommend anyone with similar symptoms to get it checked by a transmission specialist right away.