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Charging a GPS Device

Is it much of a drain on my Truck’s battery to charge my Magellan GPS device while the truck is not running?

According to the instructions, it takes 3 or 4 hours to charge the device, so driving it to charge it is not a good option. And right now the charge is so weak that the GPS doesn’t run while charging.

The Magellan doesn’t come with an A/C charger but it does sell separately and I’ve ordered one, but I would like to be able to use this thing tonight.

Most GPS units I have seen charge at less than 200 milliamperes. So if you charged it for 5 hours at 200 mA, the truck battery would lose 1 amp-hour of charge. Most starting batterys are rated at 40 amp-hour and above so it is unlikely to discharge the battery to the point where it would not start the truck. As a precaution you might charge the Magellan for a couple of hours; run the engine for 10 minutes or a short errand; and continue charging until the green ‘fully charged’ light comes on. Alternately, you could put a battery charger on the truck battery while charging the GPS or you could use one of those ‘booster/jump’ battery unit to charge the GPS while it is plugged into AC line voltage.

More than one way to bypass the accessory market.

It’s an infinitesimal drain on the battery. Don’t worry about it. You do have to make sure the cigarette lighter actually gets power when the ignition is off, since they don’t on some cars.

Just out of curiosity, which unit do you have that you can recharge? I have a Triton that I don’t think I can recharge the batteries with directly. So I have a lighter-port splitter where I can plug the unit itself into a usb power slot, then I have a battery recharger and my satellite radio plugged into it. I’ll have all of them running when I’m camping I’ve never had any problems.

"And right now the charge is so weak that the GPS doesn’t run while charging"
If it did not do this while new you need to replace the battery, as it will only get worse and may never get to the point it is fully charged, and may degrade to the point it does not work at all.

To GreasyJack - I have a Magellan 3100. The instructions say to recharge it with your car’s power port for 3-4 hours, but they also sell an AC “wall charger”.

I don’t think the battery is replaceable, so I’m probably stuck with what I have.

I got this as a gift and never really paid much attention to the details. I guess it’s time for me to read the manual.

I have left my cell phone plugged in to the lighter on my car overnight with no problems. I’ve also left a radar detector plugged in for days on end without any problems. I doubt the battery in the GPS device is enough to cripple the truck’s battery. Charge it up without fear.

I have replaced many batteries in things, it may require a soldering gun, but I would have to think it would not be so hard for a gps unit. rtfm and let us know.

They may not appear to be replaceable, but most any electronics tech can do a little disassembly and replace the batteries.  Doing some on-line searches for your specific make model and "replace battery" may turn up some specific instructions

I have a Garmin portable CPS, got it for Christmas. I charged it 4 hours from my cigarette lighter while parked in the driveway and had no problem. I plug it up when I use it and it is still fully charged.

I don’t understand why GPSs need batteries anyhow, unless you use them on your bike or for hiking.

Sorry that this is irrelevant to the original poster- you’ll be fine to charge it with the engine off. (How many 4 hour trips do you take anyhow)

Well, Bob, I imagine they need bateries to maintain the settings much like the radio in your car.

My main use of battery power is to bring it into the house and program the next trip.

Another reason, is to be able to use the unit without plugging it in.