MD88 CREW HAD ELECTRONIC INTERFERENCE THAT AFFECTED THE ILS NAV DISPLAY.

Narrative

WHILE ON AN INTERCEPT HDG OF 200 DEG FOR RWY 18L CVG AND 12 MI OUT; THE LOC CDI INDICATED FULL SCALE DEFLECTION TO THE R FOR COURSE INTERCEPT. THE MAP DISPLAY ALSO INDICATED A CONTINUED 200 DEG HDG FOR COURSE INTERCEPT. NAVAID WAS PROPERLY TUNED AND IDENT. IN VISUAL CONDITIONS; THE 200 DEG HDG LOOKED O.K. FOR COURSE INTERCEPTION; EXCEPT THAT THE NAV COMMANDS INDICATED THAT WE STILL NEEDED TO 'CORRECT TO THE R' EVEN THOUGH WE HAD ALREADY CROSSED COURSE CTRLINE (VISUALLY). ABOUT 5 MI OUT AND L OF COURSE; WITH NAV AND CDI COMMAND TO CONTINUE TO 'CORRECT R;' WE DISCONTINUED USE OF THE ILS GUIDANCE; ALIGNED TO THE L VISUALLY FOR THE REMAINDER OF THE APCH AND LNDG. AT ABOUT 1 NM ON FINAL; THE CDI AND MAP DISPLAY INDICATED PROPER COURSE ALIGNMENT. AFTER LNDG; I ASKED THE FA IN CHARGE IF SHE HAD SEEN ANYONE USING A PERSONAL CELL PHONE DURING APCH. A PAX IN SEAT #XD HEARD US TALKING AND TOLD US THAT THE PAX IN SEAT #YD WAS USING A PHONE (PERSONAL) DURING APCH. WHEN ASKED; HE ALSO SAID THAT SHE HUNG UP HER PHONE JUST PRIOR TO LNDG (THAT SEEMED TO EXPLAIN THE PROPER COURSE GUIDANCE AT ABOUT 1 NM ON FINAL). I'VE ASKED THAT OUR COMPANY BE MORE EMPHATIC IN THEIR PA'S ABOUT NOT USING PERSONAL CELL PHONES ONCE THE BOARDING DOOR HAS BEEN CLOSED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE CREW WAS FLYING AN MD88 ACFT. THE FA NOTED THAT THE PAX HAD VIOLATED REGS BY TALKING ON HER CELL PHONE DURING TAXI OUT. THE FA TOLD HER THAT WAS NOT ALLOWED. THE ELECTRONIC INTERFERENCE AFFECTED THE LOC DISPLAY. THIS ALSO CAUSED A LIKE ERROR MAP SHIFT ON THE MOVING MAP DISPLAY. ALL PROBLEMS STOPPED WHEN THE PAX TURNED OFF THE CELL PHONE. THE CREW WAS LUCKILY IN VMC CONDITIONS THIS DAY. THE CAPT IS WORRIED THE NEXT TIME MAY BE IN IMC. THE CAPT WOULD LIKE TO SEE A MUCH STRONGER ENFORCEMENT POLICY BY THE ACR AND THE FAA ESTABLISHED.