I had one experience with this problem and I’m wondering if anyone else has seen. I have found other forums with similar complaints but more so with Honda. My trunk is a 2012 Silverado LT with On Star & Bluetooth. Recently one morning mu remote key would not work 100%. I had to get very close to the vehicle or be inside of it for it to work. My wife had the second remote 170 miles away. The first thing I did was change the battery, no avail, and then I went to the store and bought a brand new battery, same results. Driving to the dealership, the Tire Pressure Monitor System (TPMS) started to signal that it lost communication to the TP sensors. The dealership looked it over for about 45 minutes and tried everything and determined that the Door Lock Controller (DLC) was going bad and the part was ordered. The TPMS shares the DLC with the key fobs. Everything else on the truck worked fine. At the dealership I pulled out my GPS (Garm??) that was in sleep mode and plugged in. It’s a unit with traffic updates and the receiver is in the 12v power cord. As I entered my destination the unit was searching for satellite signal and it finally failed to connect. I unplugged it, rebooted it, and even deleted some of the database I had in it. I called over the service rep and he was baffled. He didn’t know much about them. For the next three hours and 170 miles later the GPS and the TPMS was out and the remote was iffy. Having three hours the think about it, it was too coincidental, I unplugged the GPS walked about 75 feet from the truck and BINGO, the satellite signal was restored. Walking over to the truck the remote worked perfectly and the TPMS was fully restored. It has not happened again in the two weeks since it occurred. Conclusion, somehow the GPS or the Door Lock Controller was putting out an RFI even though both are receivers in their own right. I know Bluetooth was working during this ordeal but I do not know about On Star. My 40 year career in telephony was all trouble shooting problems and this one is a strange one, but it definitely was a real problem. I know there are millions of GPS out there and most will never see this problem and I may never see it again. It is a FYI should you ever get into the same situation. Google search GPS and TPMS and you’ll get hits.