I'm sorry to say it wont stop w/ the service brake warning, it will grow like cancer in your truck. Next you will see the parking brake on, traction control wont work, trailer brakes, then the electronic start will start to go out. I have been having this issue on my truck as well (1028 Power Wagon 6.4). I has been in the dealer 3 ties for the same problem. The last time it was there for 17 days. They cannot fix the problem, they flew out star mechanics and still hasn't been fixed. It has been going on for 6 months. I am trying to have FCA buy the truck back, but they want to "fix: it again. the problem is they wont supply me w/ a rental car.
My first question is this, have you done any aftermarket programming to your truck? If you have done aftermarket programming, then that could be the problem right there. If the answer is no, then you've likely got a lemon. Your experience sounds pretty ******, but that doesn't mean it's gonna happen with this guy's truck.
Also, dealerships don't fly out ANY mechanics. If anything, the dealerships send data to the manufacturer who diagnose the problem and send the way to fix it.
As for your "rental", if you bought it from a Dodge dealership, I don't know of any, at least here in AZ, that won't give a courtesy vehicle if they have to keep it longer than a day. It's actually in your paperwork. Mine provided me one when I had mine in for last service and they only had it for a day, but I told them there was sfuff I absolutely had to do that day.
Hope you get this resolved, but done be telling this guy it's gonna happen to his truck when there are thousands of 2018 PW rolling the streets and numerous owners on this forum who haven't had your issue.
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