Garmin 340 problem with power

[MickDB1]

Hello there
I am almost sure I have managed to blow up my 340 12v power supply feed into the unit.
It dont worky no more anyway
Is it possible to power it up with the lead, like the usb into to back of the garmin unit using a 5v supply from a cig socket reducer
I am not sure how many watts draw
Or has anyone used a car 12v cig plug lead to the unit and it been successful please??
Thanks if you know owt or have tried and found something works

 

[Robbiem]

Hi
I use the mini usb cable supplied with my 396
Powered from a usb Apple phone charger - a 5v supply from a 12v cigarette lighter should be fine.


Sent from my iPhone using Tapatalk

 

[Mzokk]

Check that the transformer is toast first by checking with a multimeter. If there is power to the two pins then make sure that they are not sticking. The pins sometimes get stuck. They are mounted on little springs and a bit of WD40 and a bit of poking usually solves the issue. If the transformer is defective then a Garmin lead is £35. But a little 12v to 5v step down transformer can be had from Amazon or EBay for £5-10. It’s just then a matter of cutting the pinned connector lead off your existing transformer and soldering/ connecting the two power wires to the new box and connecting the new box to your battery/power supply. You can use a usb lead but this is delicate on those units and if it gets damaged you can’t connect the unit to your computer or charge it. Also the unit is not waterproof with the usb lead hanging off it.

 

[MickDB1]

Thank you very much.
OriginaIy found a spare lead in me box o bits, connected it all up and it worked for 30 mins.
After it flashed and stoped I realised I had cut the power reducer off the found lead so it got 12v straight into the unit........ I will try the spare lead off me garmin car one. I just didnt want to bugger owt else up.
Not famous for my electrical expertise

 

[Mzokk]

Thank you very much.
OriginaIy found a spare lead in me box o bits, connected it all up and it worked for 30 mins.
After it flashed and stoped I realised I had cut the power reducer off the found lead so it got 12v straight into the unit........ I will try the spare lead off me garmin car one. I just didnt want to bugger owt else up.
Not famous for my electrical expertise

Hopefully getting 12v hasn't toasted the little unit.

 

[er-minio]

They might have resettable fuses. Fingers crossed, but in case let it sit for a while.

 

[Mzokk]

I had a good poke inside a 390 when I replaced the screen. (basically the same unit as a 340)

Thread 'Reparing a Garmin 390LM'

Mar 12, 2024

I have two of the little Garmin 3XX series Satnav's (a 340LM and 390LM) that I use on my old R1150GS. The 390LM gets the bulk of the and has been fine for many years I inherited it in 2016 as it came with a 2014 Kawasaki 1000SX that I bought. I bought the 340LM as a backup. Anyhow about a year ago it stopped reading the micro SD card in the unit and I was out last Friday around the Glens of Antrim and it did this.


Just a plain white screen.

Anyhow when I got it home I connected the unit to the computer and it was recognised by Garmin Express and Basecamp and continued to...

• Mzokk
• Replies: 4
• Forum: Zumo 340/350LM

• 

and don't remember seeing a fuse but it would be unusual for it not to have some sort of internal protection. Hope you get it fixed as they are great little units...........dare I say better than a Zumo XT for actual navigation.

 

[MickDB1]

Thanks for the tips and advice.
I think using a car power supply to the socket at the back seems to work, well it works for 10 m . Not tried it on a decent rideabout.
Cheers

 

[MickDB1]

Thanks again for the tips. The car Nuvi gps power lead (with big 12v plug and a green led light) works perfectly and constantly. I tried a usb lead pluged into a car 12v adaptor to 5v usb. Worked for a while then kept switchin off and back on again. So geat news for me and just keep me power bits out of the rain.
Taa very much