Question about Magellan RoadMate 300 GPS Receiver

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Won't Power from Cigarette lighter

I cannot get power once the unti is mounted and plug into the car power jack. Could it be anything other than a bad power adapter?

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Re: Won't Power from Cigarette lighter

Recently I had a similar problem with my 300 - worked fine with AC power, but was intermittent with the power point in my truck sometimes it wouldn't power up at all in the truck).

I used a small nail file (steel wool would work too) to break the "glaze" on the outside of the small plug that plugs in to the unit on the power cord. It seems that it wasn't getting a good ground. Has been working great ever since - worth a try.

Posted on Feb 09, 2008

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If this is a cigarette lighter plug, the fuse may be blown. Unscrew the top where it plugs into the cigarette lighter and check the fuse. But, more than likely the fuse in your car for the cigarette lighter is blown. Check the car fuse first.

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Car power supply for Garmin nuvi 755t does not work. Not sure if its the Wire, mount Adapter or other.

I assume you have checked the cigarette lighter to be sure it's working.
The most likely problem is the fuse in the power cord/charger. The plug which goes into the cigarette lighter socket has a ring at the end of it. Unscrew the ring, taking care not to lose any small parts, and it comes apart. Replace the fuse and it should be ok.

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Hello :

I think you have a problem with the charging jack . For that you need to call Garmin or get your device serviced .

please rate !

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When I attach my garmin nuvi 760 to the car mount and plug it in the car charger it will not power off and on when the car turns off and on. For example if I turn the car off the garmin continues to charge...

This is telling me that your cigarette lighter socket has +12VDC applied to it all the time EVEN when the ignition is turned OFF. This is not the fault of your Nuvi. On some cars, like Hondas, the cigarette lighter socket powers off when your ignition is turned off.

If you want it to turn off with the ignition, then you will have to power it from a +12VDC source that is controlled by the ignition.

- Jim

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You should be, Check to make sure the fuse isnt blown on either the cigarette lighter plug or in the plug that has the wires coming out of it.

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Garmin NUVI 660 power problem.

To charge a nuvi, use one of the following methods:
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  2. Connect the USB cable to the nuvi and the computer. The computer will charge the nuvi as long as the computer is on. However, the unit will be in Mass Storage Mode and normal operation is not possible.
  3. Connect the AC power cable and the nuvi to a wall outlet.
Please note: All of the nuvi series will come with a suction cup mount and vehicle power cable to charge the nuvi. However, only some of the nuvi models will come with an AC power cable and/or USB cable. If they did not come with the nuvi, they would be optional cables and would be a separate purchase. Garmin only recommends using an AC power charge that is purchased from Garmin. Third party power cables may not charge the nuvi. These cables may be purchased from Garmin or Garmin's dealers.

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I used another charger in house and charged battery must be the car charger adapter I haven't used it yet but I will today and let you know if it works

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My garmin street pilot 330 will not power on

I've had a couple of Garmin C330 units and a C340. They're good quality except for the flimsy power plugs. My first one out of the box had a defective plug which made intermittent contact when I plugged it into the lighter. Tightening the knurled nut on the tip of the plug helped somewhat, but didn't fix it completely. It became a non-issue after I bought a friction mount which came with a better cord and plug. The friction mount also stopped the problem of the suction cup constantly falling off the windshield.


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Installation / wiring

Yes, you can do what you said above. The only issue I see is that you should still add an inline fuse between the GPS and the power source you will be connecting it to.** SEE NOTE BELOW **
The cigarette lighter plug has a fuse in it. Most of the fuses you have in the car start at 5 Amps and go up in value, like 10A, 20A, etc.

The problem is these values are way too high should the GPS have a catastrophic failure or the GPS power leads get pinched or shorted to ground. You'll burn up the GPS and its wiring before the auto fuse blows.

You need a low rated fuse (probably 1/4A) inline with the GPS. This will give you adequate protection. You can buy inline fuse cords at Radio Shack.

** NOTE **
Check to make sure that the DC output of the cigarette adapter is indeed +12VDC and not some lower voltage indicating that there is an internal regulator circuit. I took a look at the 660 owners manual and it says the GPS input voltage is +12VDC, so you should be ok. I also hear there is some electronics inside of the cigarette lighter plug. It may have to do with charging the internal GPS battery. You could always take apart the cigarette plug and remove the internal board and use it in your hard wiring to your vehicle.

Once you get it all working, you could duplicate what you built for another vehicle. You can buy the cigarette adapters online.

Please let me know if I can be of further assistance to you.

Good luck!
- Jim

Feb 13, 2008 | Garmin Nuvi 660 GPS Receiver

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