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stereoaz, Car Electronics Technician
Category: Car Electronics
Satisfied Customers: 113
Experience:  35 years in car audio,my shop won iasca world title ,custom fabrication,expert installer.
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Have a dash installed (after market of course) in my Mazda

Customer Question

Have a dash installed (after market of course) in my Mazda Miata, the Garmin/Kenwood DNX 7140 continously requests I update its US maps.
How can I do that when Garmin site says they are no longer available. Seems it is mostly an issue of Garmin going exclusively to SD cards whereas the DNX 7140 takes a CD.
Submitted: 1 year ago.
Category: Car Electronics
Customer: replied 1 year ago.
Is it possible to downloan maps for a DNX 7180 or so write the file image to a CD. If so how do I get the authentication data required to activate? Assuming that fails I do not want to mess up my mapping so the system ends up not functioning at all!!!
Expert:  Russell H. replied 1 year ago.

Hi, thank you for contacting My name is Russell. I will do my best to provide the right answer to your question.

I would say the only chance is to download the newest maps to a CD, yes, that makes perfect sense as something to try.

As for a perfect guarantee that it won't foul up your old DNX device... that cannot be entirely ruled out. Any old device may 'break' at any moment...

If the map update file is available on the CD, the normal updating process should read them and either reject them if they're unsuitable for use, or accept them and use them if they are indeed the right map update files for this model.

Customer: replied 1 year ago.
This is what I expected but not useful because Garmin has an authentication process which is required to activate any download/install. As an elect/computer engineer, Your 'I would say....' is not useful information. I guessed what you said in my question.
Expert:  Russell H. replied 1 year ago.

Well, then follow the procedure for updating this type of (CD-only) device.

Or does this model really only have a CD drive to update through? after all, many such Kenwood devices have a 'hidden' USB port, sometimes in back of the device so as to require pulling out or dismounting the device from the dash, to access it and do the update.

Should I do research on whether your model has such a USB port? or would it be a waste of time in your opinion?

Customer: replied 1 year ago.
Garmin's site says no update available. BUT yes, there is a USB port on the back of the unit. Do you know any more than I do?
Expert:  Russell H. replied 1 year ago.

The specs listed for your model the DNX 7140, says it has these inputs:

USB input, rear A/V input, rear-view camera input

and can play MP3 files on its USB input.

So I suspect the solution is, the answer to your question would be, to update by way of a small-capacity USB flash drive on the USB input.

Expert:  Russell H. replied 1 year ago.

This video has a procedure for updating maps on a similar model through USB port:

though I admit I haven't watched it through... to be honest, it's about time I retired to bed, in my time zone. I can resume this case in the morning, if that's all right with you - and my head would be a bit clearer then.

Customer: replied 1 year ago.
Got lots of those around here. The issue is if I attempt that is the USB able to take map inputs and if so can I purchase a compatible mapping on an SD or download, and download it to the USB and then properly authenticate it. If you do not know any of this I will have to call Garmin. Apparently you don't know the answers to even these basic questions.
Expert:  Russell H. replied 1 year ago.

If it's an SD card update, you just boot up the device with the SD card in it already, it reads the files, and that's it.

But for a USB update... call Garmin, it's too late in the day for me to explain it. Thanks for your patience, and I have Opted Out of this case, for now at least. Good night.

Customer: replied 1 year ago.
As said you don't know even what I did before using your service. The DNX7140 to my knowledge updates solely via the CD, not the USB port which also to my knowledge is strictly an output for multiple other functions of that unit. A waste of $16.