1996 E320 CEL will not illuminate. When scanner is plugged in, there is no communication between the vehicle and the scanner. I also notice that the cruise control does not work, and the car idles really high...up to 1200 RPM. I have checked all the vacuum and I don't see any problem. I have replaced the crankshaft sensor, and many other related parts. I do not want to continue replacing stuff until I am able to scan for codes. I will appreciate any help.