Ford: 2002 FORD F-150 CREW CAB PICKUP, 2 WHEEL DRIVE, crew cab pickup, ford f 150

Question
LAST WEEK i GOT INTO MY TRUCK STARTED OK, RADIO ON,HAD RECENTLY RAINED SO I HIT THE WIPERS TO CLEAR THE WINDOW, THAT WORKED. AS SOON AS I PUT THE TRANS INTO REVERSE THE RADIO QUIT,STOPPED PUT INTO PARD RADIO STARTED TO PLAY,PUT INTO GEAR AGAIN AND IT QUIT SO I CHECKED THE WIPERS AND THEY DIDN'T WORK EITHER IN GEAR. RAIN HAD STOPPED SO I WENT AHEAD AND RAN MY ERRANDS,CAN LIVE WITHOUT RADIO. RETURNED HOME SHUT ENGINE OFF AND ELECTRIC FAN STILL RUNNING,KEY OFF,NEVER BEFORE HAS IT DONE THIS TURNED FAN SWITCH TO OFF AND FAN QUIT. MADE CALLS TO ALL THE LOCAL DEALERS AND NO ONE HAD EVEN AN IDEA, CALL 800 # FOR FORD AND NO CLUES THEY'RE NOT TROUBLE SHOOTERS BUT STARTED A FILE ON MY TRUCK. PLAN WAS TO TAKE TO DEALER ANYWAY THE NEXT DAY. WENT OUT THE NEXT MORNING TO GO TO DEALER AND EVERYTHING WORKING FINE AGAIN AND NO TROUBLE SINCE,AND BEEN ABOUT 10 DAYS. ANY GUESSES JUST IN CASE IT HAPPENS AGAIN?. THANKS FOR ANY HELP YOU MIGHT HAVE,  JIM  

Answer
Jim first turn on your head lights and go under the hood and wiggle the battery cables hard to see if they are loose or if the head lights flicker if they do you have a poor ground or the small ground wire has a poor conection. let me know.  good luck