ACR MLG TRACK HDG DEV ON STAR INTO PHX.

Narrative

FLYING KARLO 3 ARR INTO PHOENIX SKY HARBOR INTL; CAPT IS FLYING. CAPT DESELECTED VNAV (FMS) FOR DSCNT. I WAS MONITORING NAVAIDS XCHKING FMS IN LNAV. OUTBOUND FROM DRAKE ON 168 DEG RADIAL; I TUNED UP SRP FOR INTERCEPT AS PUBLISHED. SOMETHING DIDN'T SEEM RIGHT XCHKING FMS LNAV WITH SRP; BUT NOT FAR ENOUGH OFF TO BE OBVIOUS. I SWITCHED BACK TO DRAKE AND WE LOOKED GOOD. I BROUGHT MY CONCERN TO THE ATTN OF THE CAPT AND HE DESELECTED LNAV (FMS) AS WE DOUBLECHKED SRP FREQ SELECTED. IT WAS VFR AND WE HAD PHX IN SIGHT AND EVERYTHING LOOKED CORRECT TO US AS REF TO SRP. WE BEGAN TO DOUBT THE FMS. AT THIS TIME WE BEGAN TO TURN TO INTERCEPT SRR 312 DEG RADIAL INBOUND. AT SAME TIME; CTLR CALLED AND SAID 'ARE YOU RNAV EQUIPPED?' REPLY; 'YES.' 'ARE YOU FLYING IT?' REPLY; 'NO; WE'RE TRACKING SRP INBOUND.' 'SRP IS OUT OF SVC; WE'RE RADIATING THE NAVAID AT THE FIELD ON THAT FREQ; YOU'RE IN LUKES AIRSPACE TURN BACK E.' AT THIS TIME WE TURNED TO CORRECT BACK KNOWING FMS WAS CORRECT AND I (FOR THE FIRST TIME) IDENTED SRP. IT WAS NOT THE PROPER IDENT. SRP IS 5 NM E OF FIELD AND THIS WAS POINTING AT THE ARPT. NO NOTAMS STATING SRP OTS ON FLT PLAN. I THEN TUNED UP ATIS AND IT RPTED 'SRP OTS.' BUT; STATION RADIATING ON THAT FREQ POINTED WITHIN 5 NM OF POS 'LOOKED' GOOD. AFTER THIS; CTLR WARNED FOLLOWING ACFT THAT SRP WAS OUT AND THAT FREQ POINTED AT THE ARPT. I SHOULD HAVE IDENTED THIS ENRTE STATION BUT I DIDN'T. HOWEVER; WHAT A SET UP!