Chrysler Repair: 2005 Caravan wont start, crankshaft sensor, solenoid starter

Question
We got in the Caravan  a little over a week ago and it simply wouldn't start.  There was one click when we keyed the ignition.  We bought the book and have tracked everything it suggests.  We pulled the starter and had it tested - it was fine.  The relay seems fine.  Put in a new battery - still won't start.  We rented the code machine from the local parts store.  No codes come up and it says to "Have a nice day!"  We have locked and unlocked doors, tried the other key that came with the car that we had put up.  We bought the crankshaft sensor but have not put it in.  Why does it not give us a code and where do we go or what should we do?  I mean the car's computer says it is fine but the car won't start!  We called Dodge and they told us to drive it in and they would check it out - please - any help or direction would be greatly appreciated.

Answer
Hi Susan,
You didn't mention which engine you have so I might miss something specific but probably not. I also assume that your problem is the starter motor won't turn over the engine.
Have you tried,very carefully to jump across from the big red wire post to the finer brown wire post at the stater motor? Be very careful though because the red wire goes right to the battery so you don't want to accidentally ground the jumper when you touch it to the red wire post. That will test the red wire/starter solenoid/starter motor (do this is neutral or park only).
Then, I would use a voltmeter or neon 12v glow light to verify whether you are getting 12v on the brown wire's post at the starter solenoid when you try the starter. If not, then check to see if you have 12v at the socket pin labelled 30 at the starter relay socket and that the relay clicks when you try the starter with the key. If you have voltage at 30 and a click, then either the relay points are corroded of the brown wire is "open" between the relay and the solenoid.
If you don't have 12v at 30 then a 40 amp fuse in power distribution center (maybe #23 but I can't be sure) is blown. If you don't get the click then an 10 amp fuse in the fuse box under the dash is blown (maybe #10 but I can't be sure) OR the park/neutral safety switch on the trans is not working/adjusted or the relay is bad.
Those are the details I would follow.
Roland