B737 CAPT REPORTS CSD FAILURE ENROUTE WHICH IS REPLACED BY APU GENERATOR. LATER APU FAILS AND FLT CREW DIVERTS TO NEAREST SUITABLE ARPT. COMMUNICATION DIFFICULTIES WITH DISPATCH REPORTED.

Narrative

FLT DEPARTED AND JUST AFTER LEVELOFF ENG #2 GENERATOR CSD ILLUMINATED HIGH OIL TEMP LIGHT AND ALSO A FLASHING LOW OIL PRESSURE LIGHT. COMPLIED WITH QRH AND DISCONNECTED CSD. REPLACED GENERATOR WITH APU AND NOTIFIED MAINT AND DISPATCH VIA ACARS. RECEIVED NOTE BACK FROM DISPATCH THAT APPEARED TO CREW THAT DISPATCH THOUGHT WE WERE STILL ON GND. LATER IN FLT APU FAILED APPROX HALFWAY BTWN ZZZ AND ZZZ1 SBOUND. ACARS MESSAGE RECEIVED NO REPLY; CREW ELECTED TO TURN BACK TOWARDS ZZZ CONSIDERING ALL ELEMENTS OF FLT MANUAL NEAREST SUITABLE ARPT PROVISIONS. MADE SECOND ATTEMPT AND REACHED DISPATCH. CONNECTION POOR AND REACHED AGREEMENT THAT ZZZ OK DIVERT ARPT; ALTHOUGH COMS VERY DIFFICULT. ZZZ WAS PREPARED AND EXPECTING OUR ARR. POSTFLT CALL TO DISPATCH INDICATED DISPATCHER MAY HAVE BEEN NEW TO POS. ZZZ POLICE INTERVIEWED FLT CREW AFTER GATE ARR AS TO REASON FOR DIVERSION; CAUSING PAX CONCERN. IT WOULD APPEAR THAT ANY INFO POLICE WOULD NEED WOULD BE AVAILABLE FROM COMPANY AND WOULD REDUCE POSSIBILITY OF PAX INCONVENIENCE. FAILURE OF APU. MECHANICAL FAILURES OCCUR ALTHOUGH LOSS OF 2 GENERATORS IN 1 FLT UNUSUAL. CREW'S TASK LOADING WAS INCREASED DUE TO NO REPLY TO ACARS MESSAGE AND NEED TO USE COMMERCIAL RADIO FOR COMS WHILE COORDINATING DIVERSION. ONCE ESTABLISHED; COM QUALITY WAS VERY POOR. ENHANCED COMS TOOLS IN THE FUTURE WOULD LEAD TO HIGHER MARGINS OF SAFETY AND BETTER CUSTOMER CARE.