Do you leave it in the intermittant position all the time? For some reason the RR's wipers will not restart after the truck is turned off and then restarted. You have to move the wiper stalk to the off position and then back to the intermittant position.
2010 RR SC, my wipers would work on intermittent but would not turn off completely when the rain stopped auto function was not working. Had a fault with in rain sensor using my Iddtool. Purchased new rain senor and installed, turned in on and works just fine with out clearing the fault. Hooked BT Iddtool after to clear the code and still works just fine. Purchased new old stock for $50.00 for the rain sensor. It is a nice feature to have working for as I live in Seattle WA an we get rain every now and the in the PNW.