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Is it safe to charge the battery connected to the car and if not what are the effects of disconnecting the battery if any ?

Thanks
 

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GregC said:
Is it safe to charge the battery connected to the car and if not what are the effects of disconnecting the battery if any ?

Thanks
No problem Greg I charge the battery without disconnecting it all the time. Just don't put it on to high of a charging rate. Ten amps for a couple of hours is great.

If you disconnect the battery all the control modules, including the radio, will lose their memorys. Still no problem. Just drive the car for a few miles to get the memorys back up again, reset the radio, clock, etc....

Hope this helps
Joe
 

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Discussion Starter #4
Rocket M5 said:
no problem charging the battery with both terminals connected. But I do recommend you to put the charger negative cable to the vehicle's body(or any ground source). Just for your safety!
Thanks,
The inspection light was totally dark as the battery had gone dead when I left the glovebox door open over night.I'm sure it must have been weak form it's winter snooze...anyways a roll down the driveway,clutch out and she started up immediately.I idled it for some 30 mins,then put the charger on her for 10 mins and the cahrged showed no current and the green "charged" light came. on...but...still no green light in the battery inspection hole.I suspect the unit is pooched...What's the warranty on the battery ? This is a 2003 car with only 16000 miles ?
 

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GregC said:
Thanks,
The inspection light was totally dark as the battery had gone dead when I left the glovebox door open over night.I'm sure it must have been weak form it's winter snooze...anyways a roll down the driveway,clutch out and she started up immediately.I idled it for some 30 mins,then put the charger on her for 10 mins and the cahrged showed no current and the green "charged" light came. on...but...still no green light in the battery inspection hole.I suspect the unit is pooched...What's the warranty on the battery ? This is a 2003 car with only 16000 miles ?
Sounds like a defective battery, Greg. Leaving the glovebox open will not do it. After 16 minutes of not touching the car it will go into "sleep mode" (consumer shut off mode) whereby it will kill the light in the glovebox until the car wakes up again.
 

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Discussion Starter #6
mdernst said:
Sounds like a defective battery, Greg. Leaving the glovebox open will not do it. After 16 minutes of not touching the car it will go into "sleep mode" (consumer shut off mode) whereby it will kill the light in the glovebox until the car wakes up again.
Yeah Mike..I thought that too..But today now I know it's toast for sure.I idled it for 30 mins then it sat for about 1.5 hours and barely started..What are these things worth...should it not be a warranty thing?
 

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GregC said:
Yeah Mike..I thought that too..But today now I know it's toast for sure.I idled it for 30 mins then it sat for about 1.5 hours and barely started..What are these things worth...should it not be a warranty thing?
I would think it is a warranty item but I'm not sure. Check your warranty book?
 

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mdernst said:
I would think it is a warranty item but I'm not sure. Check your warranty book?
Couldn't really find anything on it...looking still...
 

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GregC said:
Yeah Mike..I thought that too..But today now I know it's toast for sure.I idled it for 30 mins then it sat for about 1.5 hours and barely started..What are these things worth...should it not be a warranty thing?
Idling won't charge a battery. You need to get the car out on the highway for at least 30 minutes to charge it up. Of course, putting a charger on it will do the same thing. If toast and not under warranty, do a search for a replacement of the same rating for a lot less than the dealer will charge.
Regards,
Jerry
 

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Charged the batteryby conencting a charger to the + and - in the engine compartement. No problems after charged overnight. No need for a neww battery.

The car had been standing for 1-2 months.
 

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I use a trickle charger that plugs into the 9volt cig liter, works great and keeps the battery in prime shape over the cold winter months.
 

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Purchased a battery charger from Harbor Freight and just used it the other day when my car sat for about 3 weeks and wouldn't turn over. Had a 2 amp trickle charge on it for about 1 hour. Things fine after that.
 

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mdernst said:
I would think it is a warranty item but I'm not sure. Check your warranty book?
Battery warranties are pro-rated. Depending on age of battery. I had to replace the battery on my old 540 (under warranty) I ended up paying about 50% of the pro-rated original cost of the battery. Better than paying 100%:)
 

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A month or two ago, I went to start the car after not driving it for 2 weeks and the battery was completely drained. I hooked a Battery Tender to the car for 24hr. Nothing!!! Pissed off, I whipped out the heavy-duty charger. First, I slow-charged for 1hr then switched over to high-charge mode for a few hours then auto-mode it over-night. Voila'!!! Save myself the cost of a new Optima. :)
 
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