Hey. I'm new to this forum and owner of a Cayenne turbo 2004., I have had the airbag yellow warning light on since I replace the battery. I didn't receive any error code. And I follow the previous post on this forum tried to use the PIWIS to erase the faulty memory, it didn't work though. And I also tried to disconnect the battery, but the light still on. I bought a Maxicheck(it's more direct and easy for me to use than PIWIS) to detected where is the problem which shows control module faulty 3 and belt tensioner, passager's side, rear 4BC. also the actual value shows almost everything is "too big". So my question right now is does it means my control unit need to be replaced? And if I replace it use the used parts do I still need to do the "locking steps"(I saw people talking about the airbag lock in other post). English is my second language hope I can get everything explain well. Thanks for your help.