Ford Repair: 2003 Windstar Signal Lamp In-op, electronic module, side mirror

Question
The right front signal lamp has quit operating.  I was aware of this right away because the message center in the I/P cluster warned me right away.  Changing the bulb didn't solve the problem.  Switching light harnesses didn't work either. I took it to a garage and they tried changing the plug and that didn't help.  They suggested that there might be a ground problem.  There have been other funky things going on with the electrical system, but I don't know that this issue would be connected.  The tailgate ajar warning message has been coming up on the message center, yet the tailgate door is securely shut.  When the side door is open the driver's side mirror  light is supposed to flash but now just stays on constantly.  My biggest concern right now is to solve the turn signal issue.  Possibly all of the electrical issues are connected, but I have no idea. Help!  Thank you so much.

Answer
The turn signal cicuit for this Windstar is controlled by the FEM (front electronic module). Checking for codes in this module is a necessity to avoid unnecessary repairs or parts. There are only three items that will stop this lamp from working-the bulb, the circuitry, or the FEM.

Probably a good idea to check each module for codes; everything, and I mean everything, on your van is controlled by a module. Each sliding door has it's own electronic module, besides the FEM there is also a rear electronic module (REM).

The rear door ajar is most likely the door ajar switch for that door. Again, checking for codes may prevent replacing unneeded parts.