Garmin Charger Unit

When I purchased my Street Pilot c330 (several years ago)
it came with a mains battery charger,
Part Number : 362-00028-03

I recently bought a Nuvi 255 which did not come with
a mains charger (vehicle and USB leads supplied)
The Garmin webpage shows what appears to be an
identical charger BUT with a different
Part Number : 010-10723-00

Needless to say, the Nuvi misbehaves** when trying
to use the original mains charger. It charges OK on
the USB cable or the 12v car supply so I'm not too
concerned about not having the mains option.

But I'm curious as to whether anyone knows
whether there's some difference between the units,
such as the battery used, that's causing this.

** It appears to be switching between the icon which
shows it's 'connected to the computer' (via the USB)
and going into power mode (as it would in a vehicle).
Then it bleeps and starts the cycle over again.

I didn't leave it too long in case it damaged the Nuvi !
--
http://www.ian-stewart.eu

On 4/1/2010 3:18 PM EDT, Josiah Jenkins wrote:

The nuvi auto charging USB cable is wired slightly differently than that
of a standard USB cable:

http://pinouts.ru/GPS/garmin_nuvi_power_pinout.shtml

There is a resistor connected on the X-pin to Ground which signify for
the nuvi to enter the charging mode. A standard USB cable connects the
X-pin directly to Ground which signify for the nuvi to enter the data mode.

The StreetPilot's 'main battery charger' may be wired just for +5VDC
power while the X-pin is probably just floating unconnected. This would
probably cause the nuvi to be unable to determine which operating mode
to enter--data or charging since the data lines are floating unconnected
too.

So using the supplied cable to connect to a comuter . . .
'pin X not connected - data cable, nuvi connects to PC as
removable drive, navigation NOT possible.'

Thus allowing data transfer to / from MapSource or via
POI Loader or Win Explorer ?

Haven't tried a 'standard USB' lead to connect with the PC but
this is what happens when it's connected to a 12v vehicle supply ?

Sounds logical.

Thanks for the response.

--
http://www.ian-stewart.eu

On 4/2/2010 9:15 AM EDT, Josiah Jenkins wrote:

Yes, that's using a standard *Type-B* mini-USB connector, where pin-X is
not connected.


Sorry, what I'd previous wrote above is not quite correct. I forgot that
there are two types of mini-USB connections. What's described above is
the standard *Type-A* mini-USB connector pinout, where pin-X is
connected to Ground. I checked my cables, and I'm only using Type-B
mini-USB cables. I'm not certain about using standard Type-A mini-USB
cables. Sorry for any confusion.


The Garmin auto power adapter's mini-USB connector pinout has a resistor
connected between pin-X and Ground signifying to the nuvi that it is not
connected to a PC. Standard USB cables do not have that resistor
signifying to the nuvi that it is connected to a PC. HTH.