PopBeavers ~ Others may jump in, but here is my understanding.
When I got the second check light I was on my way back to Oregon from Arizona. I called the MB warranty folks (800-367-6372) who said if no other warning lights were on I was safe to drive it, but I might have to deal with limp mode at some point.
I returned to Oregon with no problems (actually the light turned off the next day). Soon after returning to Oregon the light came on, then went off, so I took it an RV service facility who ran the codes.
I called the service manager of the nearest MB Sprinter warranty facility, 125 miles away, and told him the codes. His biggest concern was that the RV would go into Limp Mode on the way to service facility (he was including the miles I had already driven).
I then called the MB warranty folks again, told them what they said and they arranged for the "tow".
The operators manual discusses check engine lights and limp mode.
My brother owns two large auto repair facilities and tells me check engine lights are both good and bad. Too often, he says, they come on for very minor reasons (e.g. fuel cap not on tightly). Just pay attention to the other lights and keep the warranty phone number in your contacts list I guess.