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Discussion Starter #1
I was going to search but I have a couple of problems to address so it's easier.
I just got back from a deployment and forgot to disconnect my battery. Needless to say it was dead.
I used my wife's van and jumped it. It was running fine, sort of. I checked the alternator by disconnecting my positive cable and it's good to go but the battery didn't seem to charge after a good drive keeping revs up over 2k for about 40 minutes. So it leads me to believe the battery is shot. I'm going to get a new one tomorrow.
In the mean time when I *was* driving it I didn't have any microphone for Sync (it didn't hear me), and the lights kept coming on for brake, ABS and something else I don't remember with the message "Hill Assist Not Available". I think it's a parking sensor, not sure. Lastly the auto window up/down wasn't working.

Lots of questions, TLDR is:
Killed my battery, sync mic no worky worky, "hill assist not available", no auto window.

I'm not going to a stealership for this so any and all help is greatly appreciated.
 

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Auto window just needs to be programmed. Put window down and hold switch for three seconds. After that put window up and hild switch for three seconds. In regards to abs and such I would say a wheel speed sensor but if your still under base warranty te battery and other things will be covered. If not replace the battery and use forsscann to clear codes and hope they won't return
 

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Battery is prob. shot from being dead for a long time with constant low drain on it.

Window reset is normal after dead/disconnected as mentioned.

Pulling the positive cable while running is a BAD thing to do, may often be lucky but there's a chance of major electrical damage any time this is done.

With all the Wonky voltages the system was subject to, odd operation/codes are quite possible. Basic reset when battery is disconnected for replacement MAY solve some, might need reset to clear afterwards as well.

Might need a trip to the Dealer for reprogramming to solve some issues, hopefully that is the worst of the problems that result.

Luck

P.S. - I've seen some comments on "New Battery" setting for the system after replacement, have the Dealer do that as well if you end up there. Charging strategy supposedly keeps track of battery age to work better. (2012 + models)
 

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Discussion Starter #4
Update:
First, thanks for the input. The window reset worked.
I went and picked up a new battery yesterday. Everything is back to normal. I'm going to throw the old one on my charger just to see if it's d.e.d. dead or just really drained. I'm going to assume d.e.d.

Lesson learned for next time.
As for pulling the positive cable though, I didn't know it could do damage. Is that something particular to newer cars? Because I know it wasn't an issue for older ones.
 

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It can totally blow your alternator and all your electronic CPU's. It also invalidates your warranty as its expressly forbidden in the user manual. its NEVER been a sensible thing to do, even on very old cars it normally blew the diodes on the alternator

Sounds like you were incredibly lucky this time
 

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Fortunately it doesn't ALWAYS cause trouble, but there is potential for anything from minor issues to major damage.

The test dates back to Generators in cars rather than alternators, they were phased out in the 60's in cars. 50 yrs later some still hear about this & try it.
 

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Always Pull the negative off first. I did it too see if the car would still run off the alternator. But the car was a late model. This is why when you jump a car you ALWAYS disconnect the negative first NEVER the positive. If your battery from a cold start dips below 9V you really do not have enough to start the car and it usually means the battery is toast. You can check your alternator and battery at the same time when the car is running . It should show the amp at 13.5 give or take Alternator should be fine. Let it run for 15 minutes. You stop the car and use your voltmeter and your car should show 11 volts or so. Open your car door so the interior light is on and if the the voltage starts to drop right away, the battery cannot hold the charge. I hate taken the battery to the auto part store for a bench test. I do not believe them anyway. They WANT to sell you a battery. In South Florida, we are lucky if a battery lasts three years due to the heat. Sailor is right, not always causes damage but NEVER a good thing to do. It would leave you with many concerns that is very expensive to diagnose. Pulling off positive is very bad, Putting back on when running is VERY VERY VERY bad.
 

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A Full battery should be at 12.6v with no load

Its virtually flat at 12.0 and will have trouble starting the car, taking it below 12v results in sulphation of the cells and reduced performance

At 9v it would be severely damaged with cells not working at all

Charging it should be 13.5 to 15v depending on battery state and temperature

All measurements should be done with all wires connected but car either running for alternator test or having rested for a while for battery test

NEVER disconnect any cable with the engine running EVER!, but yes always disconnect negative lead first when removing a battery (unless a really old positive earth system (very rare)).

The Mk3 records when battery is disconnected and engine state, plus number of starts, OBD Code resets etc, so if you do pull a wire while its running you have lost your warranty. Did you know it also records your speed, direction, G etc. for Ford or the police to analyse if you are involved in an incident?
 

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...Did you know it also records your speed, direction, G etc. for Ford or the police to analyse if you are involved in an incident?
No kidding? Neat. Was not aware we had the black box on these vehicles, but figured they had to arrive sometime.
 
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