Chrysler Repair: 1996 dodge ram 1500 pu, dodge ram 1500, spark plug wire

Question
my truck recently stalled while driving about 30 mph. it was maybe 3 minutes after it started. Now cranks but won't start. Had codes 12,31 and 45.  I disconnected battery and all codes are off now.  Exchanged ASD and a/c relays, checked wiring and hoses only visually, cranks solid just will not start. both battery terminals were rather lose, i could twist by hand and the previously not working radio now works.  Any ideas.  thanks

Answer
Hi Kevin,
I am no expert in the truck line but would suggest you answer the question: spark/fuel/compression? Check a spark plug wire for spark by putting an insulated handle screwdriver in the socket and then hold the two with the metal shaft of the screwdriver 1/4" from the cylinder head while a helper cranks the starter and you observe for spark to jump the gap during a 5 second crank. Do you hear the fuel pump run for about a second, listening at the fuel tank, when you switch the key to the "run" position? Is the valve train moving when you crank the engine (look in the oil fill hole while helper cranks, or remove timing belt top cover to inspect timing belt). May I suggest that you ask "Kevin" the other expert as he is knowledgeable of the truck lines?
The 31 code is about the evaporative emission collection system's valve but that is unlikely the cause of a no start unless perhaps one of the vacuum lines in that system were disconnected. The system is usually on the right side inner fender so look at all the hoses over there.
The 12 code means the battery was disconnected recently (probably the loose clamps).
The 45 is not a valid code, unless you have a turbo; could it have been 55 which means "end of readout" and would be normal?
Roland