I have a 2017 66 plate E220d AMG line premium plus which is having starting issues. The car went in to an independent asnit had thrown up an EML light. They identified the problem as a NOX sensor which they replaced. They then told me that the battery needed to be replaced as it had failed. The next call was that the car was having starting issues (never had issues before even when the car had been standing for a while and I got the Start Engine message on the dash). They had it connected to Mercedes remotely and it came up with 2 faults:
P061700 - Active and Stored - The electrical line A of the starter relay has a short circuit to positive
U042781 - Stored - Implausible data were received from the electronic ignition lock. Incorrect data were received.

I went to the garage today and they cleared the faults, disconnected the battery then reconnected it and the car started fine. Switched it off and it wouldn't restart and the faults came back up. There was also a message on the dash about the Parking Brake. They say they replaced the starter relay but it did the same thing. They are reluctant to replace the electronic ignition unit due to the cost and no guarantee it will fix it. Any advice will be welcomed.

 

Hiya bud, I have the exact same issue with mine. Parking brake showing and car won’t start. Any updates in terms of issue? Hope you’ve managed to get it fixed.

 

What a timely question. I have just got my car back today after being with a different garage since mid December. There was no need to replace the ignition control module as the problem was water ingress which got into the main body loom causing the wires to break down. The water came from the sunroof drains and also a leak where the loom goes through the bulkhead. Apparently the floor of the car was swimming in water. Check under the carpets!