Dead Battery
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Dead Battery
Went to go for a drive and used the remote start. Nada. Thought that was weird, opened the garage and stood there and tried to use it again, no dice.
Door locks wouldn't open so I had to use the back-up key to open the door. No lights or anything.
DMM showed 5.5 volts at the terminals.
I have no aftermarket accessories of any kind. What could have caused my battery to drain overnight?
Josh
Door locks wouldn't open so I had to use the back-up key to open the door. No lights or anything.
DMM showed 5.5 volts at the terminals.
I have no aftermarket accessories of any kind. What could have caused my battery to drain overnight?
Josh
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Most likely that you left something on. Less likely that the computers didn't shut down properly.
If the battery was down to 5.5V, it's extremely likely that at least one cell has been reversed. I'd regard that battery with serious suspicion.
If the battery was down to 5.5V, it's extremely likely that at least one cell has been reversed. I'd regard that battery with serious suspicion.
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I'm not entirely sure if something was left on. When I came home yesterday nothing was out of the ordinary.
I charged the battery for 2 hours and went for a 2 hour drive. I'm going to let the battery sit an hour or so and load test for verification.
The only thing I can truly think of is Sync powering up when one of the doors was opened last night. That caught me off-guard a couple weeks as I was dinking around in the garage later and heard the radio playing.
Josh
I charged the battery for 2 hours and went for a 2 hour drive. I'm going to let the battery sit an hour or so and load test for verification.
The only thing I can truly think of is Sync powering up when one of the doors was opened last night. That caught me off-guard a couple weeks as I was dinking around in the garage later and heard the radio playing.
Josh
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Had the same thing happen in our Lincoln. It is a 2015. Had maybe 3-4K on it. Didn't drive it for a day and it was dead.
Jumped it and took it in. Full diagnostics revealed nothing.
Been fine ever since.
Jumped it and took it in. Full diagnostics revealed nothing.
Been fine ever since.
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730 amp OE battery, results showed 750 amps @ 12.88 volts.
Alternator put out 14.7 volts during the 2 hour highway cruise. I can load test that myself at work tomorrow, but I am not overly concerned with the health of the alternator amperage.
I am thinking Sync may have powered up and then proceeded to drain the battery...... more investigation to follow
Josh
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From: Mts. S. of San Francisco
Get it charged up, then set up a test with an ammeter. It will require disconnecting one of the terminals of the battery, and inserting the ammeter in the circuit (unless you have an ammeter that can use a hall-effect detector).
DON'T try to start the truck or do anything other than seeing what the parasitic load is (or isn't). With everything turned off, it should be a small fraction of an amp; maybe 200 milliamps at the most.
If it's over that, then you can by trial and error remove the fuses for different circuits until you find what circuit is pulling all the current.
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I had something similar with a new (500 miles) Murano 4 years ago. Turned out to be the Body Control Module randomly turning everything on. The dealership had to keep it a week to catch it doing it, and even then they had to put it in a dark bay so it would be obvious.
I hate seeing that our trucks can do that as well, but I shouldn't be surprised as anything electronic can. Good luck finding it. I'd be paranoid.
I hate seeing that our trucks can do that as well, but I shouldn't be surprised as anything electronic can. Good luck finding it. I'd be paranoid.
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I had something similar with a new (500 miles) Murano 4 years ago. Turned out to be the Body Control Module randomly turning everything on. The dealership had to keep it a week to catch it doing it, and even then they had to put it in a dark bay so it would be obvious.
I hate seeing that our trucks can do that as well, but I shouldn't be surprised as anything electronic can. Good luck finding it. I'd be paranoid.
I hate seeing that our trucks can do that as well, but I shouldn't be surprised as anything electronic can. Good luck finding it. I'd be paranoid.
So, Saturday I get home and lock the doors. Later I went and with the smart key in my pocket I opened the passenger door to retrieve a new shower head. I "think" everything powered up at that point like I was going to start the engine and drive away.
Which was the similar scenario a couple weeks ago when I caught the radio was playing well after I had gotten home.
I notice Sync behaves different if you open the door with the key in your pocket versus using the fob to unlock the doors. At least mine does.
Josh
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From: Frederick, MD
You might be onto something there. We were asked if we keep the fob in our pocket and how far away we were to the SUV. Thoughts were it was being powered up. Not the case but we do go out and get stuff and just touch the handles and it will open.
Sometimes we don't lock it right away.
Sometimes we don't lock it right away.