Audio completely stops working when connecting to car mount

[BethNod]

Dear TomTom users,
this is my first post.
I recently stared using again my TomTom GO 5100 from 2016. I updated maps, core and everything, but it has a strange problem. The audio works fine as long as it's not connected to the official car mount (dock) that came in the package: as soon as I put my GO 5100 on the dock, the audio immediately stops working. What's even stranger is that this problem only arises with the dock: no matter how many times, or how rapidly I dock and undock my TomTom, when it's docked nothing works —not even the interface sounds— and when it's undocked everything works perfectly (interface sounds as well as vocal instructions). But if I connect the micro USB car power cable directly to the TomTom, it works just fine, and it recharges it.

I tried doing a soft reset (ie keeping the power off button pressed until it reboots and I head the TomTom drums), but nothing changed.
Do you have any idea about what could be the problem, or how could I try to solve it? I suspect maybe it's something related to the magnets in the mount, but it seems strange because, again, this is the official car mounting dock that came in the package when I bought it.
Could a hard reset solve the problem? In that case, can I eject the micro SD card my maps are on, reset the TomTom, and the reinsert the SD card without losing the maps and having to download them again?

Thanks for your support, and happy holidays everyone.
Cheers

 

[canderson]

It doesn't sound like a firmware issue.

I've often wondered why the x00/x000 and x10/x100 devices have so many pins on those docking connectors. Granted, they're small pins, and several are probably being used in parallel to provide the necessary current, but 20 of them? When first released, I had wondered if any of them were an abandoned concept for bringing audio out to the dock on the side opposite the power connector. If so, we never saw that anywhere here in North America. While we're working on this, I'll round one of mine up and can opener it and see if indeed all the pins are dedicated to power, or whether there might be a couple of 'spares' for which we cannot account.

So what the heck - no one has ever reported your specific problem before, so let's have a go!

First, examine very carefully the alignment of the pins on both the dock and the device. Haul out a good magnifier or whatever tool you've got, and tell us if anything looks amiss.

 

[canderson]

My oh my yes. Guess it was long past time that I opened one of these up. Back in the day, it would probably have been one of the first things I'd have done upon receiving a new device. These little docks aren't simple pass throughs for power!

Of particular interest, there are indeed pads on the side opposite the power connector that would hold connectors of two other types (J4 and J5). Any bets that there may have been a plan for audio there at some time in the past? I see a ton of places for passive components, but will pull the label later and investigate and see what else might be present.

Now I've got to find time to meter these connector pads to see if by ANY chance there's audio on one of them. If so, you'll want to be SURE to have a very close look at the pin alignment mentioned earlier to assure that there aren't any bent ones that could be shorting across to any others.

 

[BethNod]

Thanks a lot for your quick and thorough response!
In fact, that's something I also wondered myself: "why the hell do they need twenty lanes for power delivery?!"
I've just checked all the pins, on both the dock and the device, and they all seem fine —and frankly I would not have expected otherwise, since I always treat my devices with care, and my TomTom has never fallen to ground or ever got wet—. It doesn't appear there are any bent or shorted. For completeness, attached are a couple close-up images.

Since you're saying it's probably not a firmware issue, tomorrow I'll try to unscrew the two torx on the bottom of the device and open it (but only if it's an easy open, I don't wanna ruin it) to see if maybe some lanes are broken or corroded, or even probe them. Any tips on how to do it properly? Or other things I might want to check?

Thanks again for the support.
Cheers

 

[canderson]

I wouldn't do anything just yet. Need to get the board under a stereo microscope this week and see what goes where and why.

If in a hurry, might be interesting to see if there are any solo mounts available on eBay.

As to your earlier questions - yes, definitely possible to store maps on the uSD and remove/replace it, but the maps won't be disturbed if you'd like to try a Factory Reset. It will erase personal data (e.g., Recent Destinations) and will reset all of your configuration preferences back to the factory defaults, but it's a reasonable second step outside of sorting hardware. Menu/Settings/System/Reset Device

 

[BethNod]

I'm in no hurry, but I avoided looking for a new mount because I don't know the problem yet, and I don't wanna waste money on a thing that won't help me. I really hope that, if it's a hardware problem, it's related only to the dock, and not within the TomTom itself.

Also, I wanted to stress out a detail that maybe was not clear from my previous messages: this problem arises even if the TT and the dock are completely disconnected from any source of power. Like, I have my TT and dock at home, with no cable attached to either, and as soon as the device makes contact with the dock pins, the audio disappears (I can see this quickly because there are two volume settings, one for the "undocked positions" and one for the "docked" one, and as soon as I connect or disconnect the TT the audio bar jumps between the two settings). So no power is needed to replicate this bug.

I tried performing a factory reset following the steps you've outlined, but nothing changed. Maybe there are other ways to perform a reset that could change the problem? I saw online some videos of a reset performed by a combination of button presses and through the connection to TomTom Home.

Anyway, I also tested my "magnets theory", and it was wrong: I brought some strong magnets close to the back of the TT, were the mount magnets usually attach, and I couldn'0t reproduce the bug. So most likely the strange behaviour is to be attributed to the pins, or to some strange software bug.

I was also thinking: are there any mount similar to the TomTom Go 5100 click & go mount that has the same fit but don't have the pins? I saw the Go 1000/1005/1050/etc. mount is similar, but doesn't have the pins and has a hole where the power cable is supposed to be on the bottom of the device. I just wanna have a mount to use my TT in the car, I don't care if it's unconventional.

Cheers

 

[BethNod]

Also, I noticed that if I search for "TomTom GO 1000 mount and cables" on ebay, it the mount that I was describing appears, along with the cable you see in the attached image. The connector is strikingly similar to the GO 5100 one, but only four pins are present, for power delivery. This lead me to think that only the four pins are for the 5V power supply, and the other for god-only-knows what, supporting you theory.
Sadly, I could not find the part numbers of said mount and cable. But a review on Amazon may confirm that this could in fact may work (see link and image attached).
Now I'm thinking that, if the dimensions of the connectors agree, I could buy the Go 1000 mount along with the data cable and see if it works this way. If yes, it would suggest that the problem lies in the data connections of the other 16 pins not necessary for power delivery.
TomTom GO 1000 mount (with hi-res images)

 

[Arno]

I saw online some videos of a reset performed by a combination of button presses and through the connection to TomTom Home.

Please note that TomTom HOME has no functionality with your GO 5100.

(MyDrive Connect for newer models, Home for older ones.)

 

[BethNod]

Sorry, my bad. You're right, I meant TomTom MyDrive Connect. Thanks for the correction.

 

[Willy875]

the Go 1000 bracket is not compatible with the GO 5100

Only GO 500, GO 5000, GO 510, GO 5100, GO 600, GO 6000, GO 610, GO 6100, TRUCKER 500, TRUCKER 5000, TRUCKER 6000 supports are compatible with your GO 5100

 

[canderson]

I'm going to be traveling all day today, but will get back to you tomorrow.

 

[BethNod]

Not a problem at all. Have a nice trip!

Also, it's not a problem because... I solved it!
The cable with only four pins gave me the idea: what if those pins are the only ones responsible for power? I'd need to isolate the pins on my mount too... and that's what I did. I applied some electric tape to all the front pins, leaving just the first four (starting from the left, as seen from the front of the car mount) and the two pins behind not covered. Now I have a functional mount that doesn't cut my audio for some arbitrary reason, and it recharges my TomTom too, without the need of other cable pass-through, all while being solidly connected to the dock.

Now the only things remaining to be understood are:
1. What the hell was causing this bug? I mean, it's pretty obvious now that the connector is responsible, but why did this problem suddenly arose with my unit, and randomly after some years I purchased it? Could it be some sort of production defect?
2. Could having the other pins covered cause other problem, like loss of power surge protection? I don't think so, my "new" pin configuration is the same of the cable sold on ebay for other TomTom units. But you guys let me know what you think.

It's clear now that I wont be opening this unit anytime soon, because now it works. But it would be really interesting if you @canderson did go on and probe the pins to see what may be the problem. Also, I thank you for giving me the idea that the pins are the problem here – I didn't think of that before!

Thanks again for the support.
Cheers

 

[canderson]

What remains to be discovered is whether the audio is on those other pins and is being shorted within the mount, or still possibly the unit is detecting mounting and shutting off the audio. My bet is still on the former - shorted audio. That could mean a little project in the future to bring the audio out to a 1/8" jack on the mount, too!

 

[canderson]

Actually, rather than shorted, could also be that the original concept was to shut down the internal speaker if an external audio connection to the mount was detected. If the mount is signaling such a connection, then...