Truck is a 2010 F350 CCLB SRW Diesel 4X4. Been to the dealership 3 times now for the same issue. Without trying to use 4wd the 4X4 light in the dash starts blinking. Most times it's at start up of the truck. The when it's doing this sometimes you can switch the 4x4 **** and it goes into 4wd and other times it does nothing and continues to blink. If you try and get it to shift while blinking it sometimes will stop working all together (like the TC is in neutral) and tonight it tried on it's own shifting into low range at 40 MPH (lots of grinding and banging) not good. The dealer has replaced the shift motor twice. The module that controls it once or twice, checked every connector pin and wire. They had it for a month over the summer, thought they had it this time? Of course now that it's winter and I need my truck the most and need 4wd it decides to take a ***** again! Looking for some MAJOR help here. I know the tech at the dealership, he's tried everything and has a ton of time in it already and calls to Ford. Looking for something new to look for or someone who's had the same issue. Have had good luck with the truck other than this. This issue has been a total PITA! Will be glad to answer anymore questions that may help in solving this issue. HELP PLEASE!

 

Did they check into the GEM module, I believe that controls every electrical component also.

 

Take it back to the guy who has all the time in it. Tell him to contact hotline and get in touch with his FSE.

Tech needs to follow correct pinpoint tests as defined by DTC or SYMPTOM chart. Flashing generally means its an error, an should have associated DTCs. FSE will have him repeat the steps and give him the answers. If tech still incompetent at the repair, the FSE will come out and diagnose it himself.

The fact that he has changed the shift motor an module twice is a red flag.