You guys are so whacky.
The battery and alt fails are often interlinked on these, new battery likely means alt died to kill it and the old battery tun too long does that commonly on Focus cars. The ONLY acceptable test of a battery is a loadtest at proper CCA. Jumping car off with a dead battery to die the next day, do we think cars fix themselves??? Alt likely dead, trying to recharge a dead battery on these is the quickest way to fail the alt there is, it takes EIGHT HOURS to fully recharge the proper 500 CCA battery Focus uses. The alts can die in 30 minutes of that. They were never intended to fully recharge the battery from dead and Ford specifically states it in the service manuals.
ALL cars now can run a brand new battery down in as little as a month and I've seen quicker, there is simply too much memory used to keep computer settings in place. I used to sell batteries and leaving them sitting in cars with cable terminals on was the best way to kill a new battery in two years there was.
The routine end result of charging a battery is 13.2-13.5 volts but a battery can only hold 12.7-12.8 so some of it MUST drop off, it is surface charge and it drops quickly and that is way more than .25 volts. It drops to a battery number from 12.3-12.7 or so in maybe an hour or less and THEN it should stabilize to only drop slowly as mentioned.
Focus cars do not have timing chains on the zetec SVT engines. Rubber belt. How they commonly strip to bend all valves in them when not changed.
Belt chirp is commonly NOT the belt if new and so many think otherwise, I used to sell belts too. Use the range indicator on tensioner to tell whether the belt is the correct length, many sold as the right ones are way toward one end of the tensioner range and then not tight to slip. If the belt was easy to get on the tensioner then likely it is too long. Pulleys can make noise too, bad bearing or grooves stuffed with dirt to not positively grab the belt and the new one slips to make noise.
Post #5 get the alt checked, they commonly shed diodes and one missing will run a new battery down slowly in maybe a month. Run long enough with bad diode and then the regulator fails trying to pick up the lost charge, it overheats. Why you can't totally charge the battery back up completely without risk of failure. The diode package there is utter garbage.
Fix the driver first, then fixing the car becomes so much easier..........
Last edited by amc49; 05-18-2019 at 10:14 PM.