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Hotwiring Boost i450 To Car Battery
Posted: Mon Mar 20, 2006 1:32 pm
by tchovorka
What is the process for hotwiring a boost mobile to the car battery so that it is always on? In otherwords what cable do I use? Do I just run it straight to the battery? Does it need some sort of voltage regulator? etc....
How do I make the cable and how is it attached to the battery?
Thanks,
TH
Re: Hotwiring Boost i450 To Car Battery
Posted: Mon Mar 20, 2006 1:57 pm
by joesgt281
tchovorka wrote:What is the process for hotwiring a boost mobile to the car battery so that it is always on? In otherwords what cable do I use? Do I just run it straight to the battery? Does it need some sort of voltage regulator? etc....
How do I make the cable and how is it attached to the battery?
Thanks,
TH
I haven't done it yet but my plan is to just get a replacement cigarette lighter and plug my phone into it with the provided cord. I will wire this to the battery, or some other "always hot" circuit, using an inline fuse.
Hotwiring Boost i450 To Car Battery
Posted: Wed Mar 22, 2006 3:51 pm
by tchovorka
Can someone who has actually hardwired a boost mobile phone to the car battery please contact me. I need to details on what is required so that I do not ruin a phone in the process.
Thanks,
hot wire
Posted: Thu Mar 23, 2006 8:07 am
by guest220
TC
Its really very simple.You can do as above.Purchase a car charger.There is 2 wires out of it.One goes to your hot like a battery which is the eaisest Pos side and ground the other side.In my vehicle I have the hot going to the battery for the hot and the other to the side wall for the ground The phone is hidden in the air cleaner container.You can also put it under the dash But unless you run a hot wire to the battery you will have to wire it into a hot fuse.You could always have a radio installer do it to if you don't think you can do it.If you have trouble with the phone skipping time and stalling everyonce in awhile like I do be sure to put it in a place that is easy to get to to reset it.Mine does it about every 1 to 2 weeks. Hope this helps
Posted: Mon Mar 27, 2006 8:00 pm
by Guest
Won't this drain your car battery???
I am going to do this also but sometimes my truck sits for 2 days (weekend). Will it kill my battery??
Posted: Tue Mar 28, 2006 6:49 am
by Skibum
Not unless you have a bad battery to start with. The load from a cell phone is very very small. Without running the numbers, I'd say you could leave it on for a month, and have no trouble starting your car.
Posted: Tue Mar 28, 2006 8:53 am
by Guest
The battery that comes with the phone is around 800mah and it will last approx 6-9 hours running AT.
Find the amp hour capacity of your car battery and multiply it 1000 times. and that will give you the mah capacity of the car battery.
Example with 650 amp battery:
650x1000=650000/800=812.50 meaning it should last 203-304 days on a fully charged 650 amp battery.
I am no electrical engineer but I think this equates to No Problem hard wiring to a car battery.
Posted: Tue Mar 28, 2006 1:24 pm
by Guest
Thanks guys a day or two will do just fine, I think the range you gave will be acceptable
Also after thinking about it, alot of people use to have or still do have car phones that are permanently attached and I believe always on and they probably use more power then a handheld.
Thanks again.
Posted: Tue Mar 28, 2006 2:32 pm
by Skibum
Anonymous wrote:The battery that comes with the phone is around 800mah and it will last approx 6-9 hours running AT.
Find the amp hour capacity of your car battery and multiply it 1000 times. and that will give you the mah capacity of the car battery.
Example with 650 amp battery:
650x1000=650000/800=812.50 meaning it should last 203-304 days on a fully charged 650 amp battery.
I am no electrical engineer but I think this equates to No Problem hard wiring to a car battery.
Unfortunately there is no car battery that has a capacity anywhere near that, so don't expect 9 months of operation. The 650 that you are referring to is cold cranking amps... The MAXIMUM draw that can be taken from the battery if fully charged. This has no relation to the capacity of the battery.
Posted: Tue Mar 28, 2006 4:40 pm
by copter
Skibum is correct 650 would be cold cranking amps, the reserve capacity of a car battery is around 100 amps. Accordind to the example you still would not have a problem with a hot wire to the battery.
Posted: Tue Mar 28, 2006 4:48 pm
by Skibum
Correctomundo...

Hotwiring Boost i450 To Car Battery
Posted: Wed Mar 29, 2006 3:49 pm
by greattracking
Batteries for small cars (with reserve capacity 80 minutes) have about 35 Ah capacity . I measured the 12 volt current draw is 230 mA when charging my i88s. It draws 100 mA on the 12 volt when the cell battery is full. I calculated it takes 6 - 13 days to fully discharge the battery. Since the cell battery is full for most of the time, my guess is maybe 10 days or more to discharge a small car battery. This assumes your car battery is good.
If you drive a big car, the battery has more capacity (120 minutes RC) and it could last 50% more.
To prolong the life of car battery, we should not drain the car battery too much. So I think those who hot wire the charger and have small batteries should run their car at least every 3 days.
Hotwiring Boost i450 To Car Battery
Posted: Thu Mar 30, 2006 10:29 pm
by tchovorka
Just wanted to update everyone since you were such a big help to me. I was able to successfully hotwire my i450 and run the wire through the firewall with other existing wiring. I just went to Radio Shack and bought an external cigarette reciever that had a 12 foot cord on it and connected a 10 amp inline fuse on the positive wire. I plugged the phone cigarette charger into that and tucked it away. It works great and has been up and running for 5 days straight at 1 minute intervals and HotGPS turned on. No problem whatsoever on the car battery.
Thanks for all the help,
tchovorka
Posted: Fri Mar 31, 2006 10:59 am
by Guest
Just a reminder when hooking up to your wife's car, make sure the ring and DC volume is off. Otherwise you are busted when a ring comes under the hood!

need help
Posted: Sat Jul 08, 2006 2:37 am
by cindymann
I was reading the post on hotwiring with the external cigarette lighter but got completely lost on the 10 amp inline. Can someone explain this to me in detail?