Originally Posted by RichardM98

Generally, a car in limp home mode has a transmission issue. Limp home mode is designed to protect the transmission from further damage. OBD2 scanners display codes for common emission control devices not engine or transmission error codes. You'll need SDS style scanner at a dealer or MB indy to inspect/erase those codes. There are Chinese knock-off scanners on eBay which have worked for some but not others.