Hello, welcome and thanks for asking your question. My name is***** a Certified Auto Technician with 28+ years experience. I will do my best to assist you. please keep in mind that I may need to ask questions of you before I can answer. When you reply please feel free to add as much detailed information as possible pertaining to your concern.
Start Error means that there has been a malfunction of the Immobilizer System. The problem could be the key, the receiving antenna surrounding the ignition lock cylinder, SKREEM Module, ECM, or a fault in the wiring.
To figure this out you MUST have it scanned with the Mercedes or Dodge Scanner to be able to know what diagnostic path to take..
From past experience, as long as both keys are good, the most common failure is the SKREEM Module itself...
If you need additional information, don't hesitate to ask, I am happy to help as long as necessary to help solve your concern. Remember, a "Positive" Rating will not close this question, You can post a reply here whenever you want, even after rating my answer!