Why won't it turn over?

What is this?

Did you check the fuse in the under hood fuse box ? GEN / BATT fuse 10amp . Is your check engine light on ? This is a computer controlled charging system , it should have four wires connected to the alternator . 1 - the heavier wire on the back ,this comes fro the starter - the one with fusible link , you could have checked for battery voltage with voltmeter ! The three other wires in the connector are the orange one ,this comes from the GEN / BATT fuse an should have battery voltage ! The last two come from the PCM - engine computer . The gray wire is the turn on signal from the PCM an the Red wire is the control from PCM ! Charging System Wiring Diagram MOTOR Magazine Article MOTOR Information Systems

have you checked power to the starter motor, if no power check the control fuse , usually placed close to the battery fuse box , it will be around a 100 amps so should be easy to spot, if this is ok then will need to check if the ignition switch is sending power to the starter , if have power to the starter i would assume the starter is at fault.It could also be the start switch at the clutch point of starting if the rest checks out so getting the OBD codes read could point you to the component at issue , is there any sort of clicking noise or is it completely noiseless? if it is clicking then the battery may not have enough amps for turning the engine but enough to appear fully charged so get the battery condition checked for holding charge etc , hope some of this helps keep me posted if you wish and good luck

Check battery must fully charged, check starter fuse and relay Check 12 volt wire from ignition switch to starter relay in the fuse box ,then check 12 volt wire from starter relay to starter motor solenoid if if it's everything is ok then change the starter.

Or the battery cables ! Do you know how to use a voltmeter ?
Starter Voltage Drop
Do you know how to do basic automotive electrical testing ?
How to voltage drop test starter motor circuit
Electric Testing Techniques You Need to Know Here is a place to view wiring diagrams ! http://www.bbbind.com/free_tsb.html

Starter problem..

clean all connections very good ( batt post connectors,gound wire from batt to frame/motor, also clean starter connections,and alternator connections) I know pep boys checked but you cannot properly check a battery unless it has a full charge!!!!! If it wont accept a full charge then batt is bad, If it charges to a full charge and fails a draw test the batt is bad. also when a draw test is done you can have the charging system checked also to make sure batt is recieving the proper charge input. all inexpensive checks, get it running and take it to a garage, 3 min test usually not even a charge most of the time. NOT A DEALER, and have them show you what they are doing. if you are a female have a male friend go with you or have it done. I dont care what anybody says!!!!!! When it comes to a inexperienced female, the DEALERSHIP,the REPAIR GARAGES will all try to get some kind of MONEY out of you before you leave their place of business.

check ign. fuses,batt.cables if theyre tight,make sure batt.is full charge,if every thing checks ok pull starter out of car and have it checked at local part store to make sure its defect,if so replace it.

any losen weire araund starter?on starter hawe 3gray fusebel link weire and hawe to conect with same weire from batt big red weire.if are conected chek gray 3 weire by sleigty poling on weire and see if is brocken samtime brick iseide under insolation and yu cant see disconect batt before inspection

Voltage drop test starter system ( cables )
Starter Voltage Drop also try moving gear selector to neutral (park neutral safety switch )
How to voltage drop test starter motor circuit