FLT CREW OF E140 EXPERIENCE TRACK DEV ON GRABE RNAV SID WHEN CAPT'S AND FO'S FMS SYSTEMS HAVE GROSS DISAGREEMENT ON WIND DIRECTION. UNCERTAIN POS RESULTS.

Narrative

DEPARTING DFW ARPT ON THE GRABE 2 RNAV DEP FROM RWY 35L; AT APPROX 1000 FT MY FMS CDI NEEDLE TURNED AS IT SHOULD TOWARDS THE CUZEN INTERSECTION. I BEGAN A SHALLOW TURN TO THE R WHEN THE FLT DIRECTOR BARS BEGAN TURNING LEFT. I ROLLED WINGS LEVEL. THE WIND INDICATOR ON MY PFD WAS SHOWING A 128 KT WIND FROM THE SW WHICH COINCIDED WITH THE LEFT TURN GIVEN THAT THE CDI AT THIS POINT WAS SHOWING THE ACFT FULLY DEFLECTED OFF COURSE TO THE R. THE CAPT'S PFD WIND INDICATOR WAS SHOWING A 130 KT WIND FROM THE NE. HIS FLT DIRECTOR WAS SHOWING A FULL TURN TO THE R TO CORRECT FOR HIS WIND. THE FMS'S WERE FLASHING A POS ADVISORY. UPON SELECTING THE MSG BUTTON; IT SHOWED POS CORRECTING. WE NOTIFIED ATC OF THE FMS MALFUNCTION AND WERE TOLD TO LEVEL OFF AT 3000 FT. WE WERE AT APPROX 3500 FT WHEN GIVEN THIS ALT. THE CAPT ASKED FOR A HEADING TOWARDS CUZEN AND WE WERE GIVEN A 010 DEG HEADING. I BEGAN A SHALLOW DESCENT WHILE THE CAPT TROUBLESHOT THE PROB. WE WERE THEN CLRED TO MAINTAIN 4000 FT. ABOUT ONE MINUTE LATER THE FMS'S FOUND THEIR POS AND EVERYTHING SEEMED BACK TO NORMAL. WE NOTIFIED ATC WE WERE ABLE TO NAVIGATE AGAIN AND THEY CLRED US DIRECT TO GRABE INTERSECTION AND UP TO 17000 FT. THE REMAINDER OF THE FLT WAS NORMAL AND NO OTHER ANOMALY WAS EXPERIENCED WITH THE FMS. CTR CTL ADVISED US A TELEPHONE NUMBER TO CONTACT DFW TWR. DFW TWR NOTIFIED US THE EVENT WAS ENTERED AS A PLT DEV.