05 Ford Freestyle not charging battery

hmm, sounds like a bad alternator. I would start there!

What do you mean won't stay charged ? Battery dies while driving , dies over night ? Is the battery symbol lit on the dash , check charging system message on driver info center ? If it drains over night there is a parasitic draw on the electrical system ! If while driving the battery goes dead it's not charging , with a new alternator the problem is in the electrical circuitry . Blown fusible link or fuse . This charging system is controlled by the PCM - engine computer , the heavier gage wire on the back of the alternator should have battery voltage , if not blown fusible link near the battery . The connector with three wires ,one should have B+ voltage , the other two come from the PCM .

Check for blown fusible link and possible bad relay. On relay, with everything off and hot battery hook u battery and give it ten minuets or so, then feel the top of eac relay. if you find a warm or hot one Bingo!

Is this the alternator that was in the vehicle when you hooked the battery up wrong? If so, you probably blew out the voltage regulator in the alternator.

Sounds like the new alternator is not charging the battery. Once the battery drops below a certain level the car can't keep its components (on board computer) running. The ignition is now running off the battery which is fading. Soon the car won't be running at all.

As already suggested, check belt and new alternator.

A ford needs a fully charged battery to work the alternator. You may burn out the replacement alternator by hooking it up to a dead battery. Get the battery charged and have it load tested. You may have a bad battery and it should be checked. http://www.cardone.com/english/club/select/electrical/protech/tech_bulletins/PT37-0006.pdf

SOUND LIKE ALTERNATOR PROBLEMS CHECK BATTERY CABLES. MAKE SURE THEY ARE CLEAN AND TIGHT.CHECK DRIVE BELT MAKE SURE ITS NOT LOOSE OR DAMAGED.IF ALL LOOKS GOOD CHECK ALTERNATOR VOLTAGE OUT PUT AT BATTERY WITH CAR RUNNING.BATTERY VOLTAGE SHOULD BE 13.5 - 14.5 VOLTS. IF NOT ALTERNATOR IS FAULTY.

Sounds like you may need a battery once you replace the battery check to make sure the alternator is charging.

Your alternator dosent work properly rechaange it again

Have the alternator tested. Both Autozone and Advance auto will do it for free. It's probably the diode.