Question about Tomtom GO 300 GPS Receiver

1 Answer

Green Light / Dead Tomtom - Please help with component id

I have accidentally plugged a 12v supply into my tomtom 500 ( which I think is basically the same component wise as the 300 ) and blown it up.
I know through reading posts on this forum that I am not the first idiot to do this. The unit is dead apart from the green light, on inspecting the panel U24 is burnt although U25 and the board print seem ok. My problem is identifying a surface mount component which got completely burnt up.
see pic
as you can see from the picture I have removed the component which I believe to be a diode. If anybody knows the value of the component and the number of a possible replacement I would be very grateful. I am led to believe that a 1N414n might be suitable but have been unable to obtain one.
If it is a diode I would also like to know which end the anode is soldered onto, as I say any info on the component would be great.
Many Thanks

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that gotĀ 5 achievements.


    An expert who has written 50 answers of more than 400 characters.


    An expert whose answer gotĀ voted for 20 times.

  • Expert
  • 158 Answers

That diode is a reverse polarity protection diode. An 1N414 will do ( available for very very little from almost ALL electronic component suppliers.) If there is NOTHING ELSE WRONG then the tomtom will still work without this diode. Its not needed in normal operation anyway. All it does is cause the fuse to blow in the cigarette lighter plug if the polarity is accidently reversed. Therefore , with a correct supply , it does nothing !

Posted on Sep 13, 2008

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

2 Answers

Old Tom Tom can't find signal

Replace the battery!. Maximum life is two years. If you have not fully charged it by usb or ac prior to a trip and then connected it to the 12v car outlet before starting the engine the battery becomes damaged overtime.
Battery level determines the time it takes to make a connection. Always keep it charged. Never plug it into 12v car power when starting engine. This will not only shorten the life of the battery, but wiull damage the SIIRF chip.

Please rate my help++++Thanks for uising FIXYA

Jul 01, 2010 | Tomtom One XL GPS Receiver

1 Answer

Waiting for valid GPS signal

When was the last time you updated the QuickFix of your TomTom? It helps your GPS to find the satellites.
Please, do the following:
1) Install "TomTom Home" software in your computer from
2) Start TomTom Home in your computer
3) Plug in the GPS dock to your computer's USB port and place the GPS on the dock. The green light on the bottom right of the GPS should turn ON to indicate that the GPS is getting power from the dock and charging
4) Start your GPS while being in the dock. If the GPS asks "do you want to connect to computer" answer "YES"
5) The TomTom Home software will detect the GPS and check if there are any updates for it. Then you'll be offered updates to install. Some are free, some are not. Be sure you choose to update "QuickFix".

Please, report back if you need further assistance
My ID: alexocuello_

Apr 05, 2010 | Tomtom ONE XL GPS

1 Answer

My tomtom go

hello, this problem and answers is covered under the TomTom Go 300 section. Please take a look there to get an answer. Its very comprehensive.

Sep 11, 2008 | Tomtom GO 700 GPS Receiver

1 Answer

TomTom one dead

then you have a nice paperwieght!

Sep 01, 2008 | Tomtom ONE GPS Receiver

1 Answer

Tomtom one not poweringup

Lofty same just happened to me, following great deal of searching, my conclusion is that over voltage has fried regulator chip in tomtom, the reason you have green light is because at different part of power board. Approx repair cost if damage is not too bad (50% cannot be repaired) is £70.

TOMTOM will have a look for nothing, and give you a quote, if don;t want to proceed they will send it back for free also.

Good luck.

Mar 17, 2008 | Tomtom ONE GPS Receiver

1 Answer


If you have the green light lit on top of the tomtom but it won't switch on , then you have a condition commonly known as "the Green Light Syndrome". Most likely cause is blown components inside the tomtom that regulate voltage. The reason they blow is usually due to user connecting incorrect charger ( such as a 12v one for a phone ) or sometimes the tomtom charger goes faulty and instead of ouputting 5 voltas it outputs 12 volts and damages the tomtom inside. the parts are not easily repalced and require a specialist repair centre that has good experience of repairing tomtoms. You cannot repair it yourself using a normal soldering iron. Good luck.

Feb 16, 2008 | Tomtom One Europe v2 GPS Receiver

2 Answers

Tomtom 300

Have you tried resetting the unit?

small pointy object in the hole marked 'reset.'

failing that...

Sep 01, 2007 | Tomtom GO 300 GPS Receiver

Not finding what you are looking for?
Tomtom GO 300 GPS Receiver Logo

1,389 people viewed this question

Ask a Question

Usually answered in minutes!

Top Tomtom GPS Devices Experts


Level 3 Expert

7987 Answers


Level 3 Expert

60960 Answers

Will Halftowaite

Level 3 Expert

503 Answers

Are you a Tomtom GPS Device Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides