Any idea why D flashes on dash and on gear shift indicator?

 

It put the truck into limp mode. I found this information on another post:

Sounds like it's going into 'limp home mode' i.e 3rd gear only and no gearbox changes. Does the M&S lights come up simultaneously? It could be a few issues, the battery charge is too low, the xyz switch is defective or needs adjusting or just a gearbox ECU glitch.

 

Thanks! M&S lights do come on simultaneously. I'll test the battery first. Xyz switch sounds a lot more involved!

 

It happened to me once after the truck had sat for a while. It ended up being the battery wasn’t connected all the way.

 

Thanks. I adjusted the battery cable and it is working now. Flingers crossed.