Tomtom Go 720 Replacement Battery

mikealder · Posted: Fri Aug 21, 2009 6:02 pm Post subject:

My One Third Edition is out on loan at the moment so it's not going to be possible to take it to bits for a few pictures to help, that said I might have some pictures on the PC showing what's inside, I will post them later. The same process to take the device apart will apply though and changing the speaker should be a lot easier than the battery on an x20/ x30 - I haven't looked at the linked replacement speaker yet as I am mobile at the mo, one other thing to consider is fitting a line out socket to the device which a few users have done (motorbike forum section). This would let you use the device plugged in to the cars aux input, assuming it's got such a connection) - Mike

Alabama978 · Lifetime Member Joined: Mar 29, 2009 Posts: 67

Great How To Mike, I'm sure as the X20 and X30 gets older there will be a lot of use made of the article. Perhaps a Sticky might be order. Wink

One thing which you might not be aware of and that is if you deliberately posted the photos so that they are bigger when clicked they go to the Imageshack but are not viewable unless one has a subscription.

As they are I think the are pretty good anyway but thought I'd mention it in case you wanted them to supersize on a click.

DraySoft

You probably have checked already being a hardened electronics guy but my guess is that when the little board flexed it maybe cracked an SMD component. A good look around with a hefty magnifying glass is in order.

Safety Tip.
That's a good idea too to slit the original battery case and keep the plastic cover and wrap around the new battery, but please, please, be careful when cutting not to short the old battery terminals as LithIons can be dangerous when shorted, even the small capacity ones.

mightyyid · Posted: Sat Sep 19, 2009 3:57 am Post subject: I've done it...

Ok, my TT 720 works fine but for over a year, more so in fact, it has a battery life of about 4 minutes from fully charged, so was obviously shot. So I thought I;d be brave and give the battery change a go.

Mine is a European 720 but as I'm now living in Melbourne, I have the Aus maps on a SD card.

I ordered the battery from UK ebay with a seller who would ship to Oz. It took about 8 days to get here but got here fine. £17 all in and the benefit of having a UK bank account still.

Following these instructions ot the letter I opened the back. My few comments/tips as I did it.

I also bought a Torx 5 bit head which was all that was needed and I used tweezers virtually all the time - a massive help.

Getting the front surround off was hard but I had to use a flat balded very thin screwdriver to force it open. Then it was fine.

I took the small cable out (two wires I think) on the first screen - it made life easier when reassembling.

There are 4 screws to remove the PCB so make sure you remove all of them. One has a black (earth?) wire under it which you need to ensure goes back over the PCB when you replace it.

The flat cable was fairly easy to get off - using the tweezers to lift up one edge of the bracket the other popped up at the same time. Very similar to those clips that hold in computer memory.

The battery was stuck very tightly - I used the tweezers and then the flat end of the tweezers to slowly prise it up. It did come up OK, but make sure you use the tweezers away from any areas of the PCB which are close to the point of the tweezers. By the way, it is suggested you cut out the battery but for me it was impossible to do this, since the join of the cover on the battery was underneath and cutting, for me, would have been worse than peeling it up.

Battery up and out. I replaced with the new one, slighter thinner, just using a rolled piece of insulating tape to hold it in position. Cable on the battery was longer but that's OK so I left it.

Reconnected everything ensuring the black cable was over the PCB and thus screwed down with the other screws. Getting the PCB back into position was a pain, and making sure the USB port etc all lined up helped and hindered in equal measures.

There is a black bit of tape covering the flat ribbon - which I forgot to replace. I'll leave it for now and see if this was just helping to hold the cable in place (which I think is the case) or whether I need to dissasemble it again which I'm loathe to do.

Turned it on and it fired up fine. It's now charging in the USB base by the computer and I'll leave it for a while and see what happens.

It was like you had done a full reset - Home was longer registered and my custom icon was back to default, but I'll use it in the next few days and see if I notice any issues or indeed what the battery life is like. It's been so long ago that I have no idea what to expect...

There was a sticker inside the case too, advising of a build of 03/2006. I know I had one of the first ones I think - would this be right?

Hope this helps you all. I did not take pictures as there's no need as the ones on the first page are perfectly good...

satchippy · Occasional Visitor Joined: Aug 29, 2009 Posts: 4

Hi Guys
We have a 720 & 920 ,The 720 will not switch on at all ,anybody got any clues as to will it be the battery or switch,if its the switch can I fix it myself.
Thanks

Andy_P · Posted: Mon Sep 21, 2009 2:27 pm Post subject:

If the battery is completely dead it might be preventing the unit from starting. If you are prepared to experiment, it might be worth dismantling, removing the battery completely, reassembling, and then seeing if you can get it to power up using the car charger. It probably won't run properly, but you should be able to get it to switch on.

I would have thought it would be quite hard to source the power switch itself, and equally difficult to resolder in a new one if you did.

I would recommend satnavshop for a repair quote.

mightyyid · Posted: Mon Sep 28, 2009 5:02 am Post subject:

I thought I should add that since changing the battery the unit has been working perfectly and the other day I used it without a charger, and it lasted well over 2 hours. Brilliant. When you are used to 5 minutes, this makes a big difference.

Looking back it was faily easy but you need good light, good steady hands and probabaly a bit of luck with your unit opening easily etc.

No reason to change now, since I still think this 720 is tops...

psyskiesman · Posted: Sat Oct 03, 2009 12:13 pm Post subject:

My 720 battery life was down to a couple of minutes so I bought a new battery on eBay. Followed all the advice on this forum, BUT, and this is a very big BUT. Do NOT attempt to change the battery unless you are willing to accept that you may damage your unit! I tried to get the battery off the circuit board but it really is stuck solidly. Next tried carefully cutting open the black wrap around the battery; it's still stuck solid! Now I tried to prise the battery out of the shrink wrap; it shorted with a gas escape and fire!!!! I reassembled the unit without reconnecting the battrey and tried it in the car. All I get now is the splash screen, no GPS. Disassembled it again and reconnected the old battery, still no joy but the splash screen has now been on forover an hour! Go figure! So there you have it; one wrecked 720. Think twice; ps have new 720 battery for sale.

mikealder · Posted: Sat Oct 03, 2009 12:25 pm Post subject:

As a direct result of the last post and a few others in this thread I am going to edit the post that contains the instructions for taking the device apart.
Cutting in to the LiPol battery is very dangerous and will result in a fire, pulling the battery directly off the PCB will damage the tracks.

I was reluctant to post the instructions about how to take the unit to bits due to users damaging themselves and/ or the units, perhaps its time to reconsider if this thread is of any use. To counter this argument though quite a few users have fixed faulty devices - Mike

Brad99 · Occasional Visitor Joined: Apr 12, 2008 Posts: 11

I've not taken my 530 apart, but I work on surface mount circuits most days and have come across the 'glue' problem many times. The usual technique is to warm things up a bit before pulling the glued item off. A hair drier should work OK. No guarantees mind.

DraySoft · Posted: Sat Oct 03, 2009 8:56 pm Post subject:

Bradd99,

I don’t think using a hairdryer is a good idea, it would be very easy to heat the battery up to a dangerous temperature with disastrous consequences.

I started this topic and do not think you could apply enough heat to soften the adhesive without damaging the battery or the components on the PC. As I said previously I also worked in the electronics industry for many years working on electronic instrumentation with and without surface mounted components.

I still think the only way to remove the battery is to VERY carefully cut the outer sleeve making sure not to damage the battery in any way i.e. flexing, cutting or shorting.

You tube shows many batteries being abused and the resulting explosions / fires.

The moral, do NOT damage these batteries in any way, do NOT attempt their replacement if you are not totally confident in your abilities.

Andy_P · Posted: Sun Oct 04, 2009 1:55 pm Post subject:

mightyyid · Posted: Wed Oct 07, 2009 6:03 am Post subject:

Having been able to speak from authority and knowing that every unit is different, I would say that to change the battery was relatively easy but the hardest part was removing the battery.

As I outlined above, it was impossible for me to have removed the black tape but by very carefully sliding tweezers under it and applying pressure, the glue slowly started to come away and bit by bit the battery became unstuck.

Obviously doing this in a warm room where the unit has been some time will also be easier than bringing the unit in from the cold car and doing it when cold, so use natural heat to your advantage.

And while some will be too hard to remove, I bet anyone can do it with some finesse and patience.

Calomax · Posted: Wed Oct 07, 2009 8:36 am Post subject:

What is hard to understand is, when it's a known fact that batteries have a limited life, why TomTom designs its devices without being able to simply click the case open and unclip the old battery then clip in the new one.

Manufacturers of mobile phones and other portable electronic devices have done it for years. Although not iPhones and iPods I believe.
_________________
TT Go Essential

Wazza_G · Posted: Wed Oct 07, 2009 8:54 pm Post subject:

Would someone give Calomax a good slapping for coming up with a common sense idea!

You should be ashamed of yourself coming up with such a logical, well thought out idea, that in a world where common sense is nonsense! Rolling Eyes

You'll never get anywhere as long as you keep coming up with sensible ideas like a easily replaceable battery...

Calomax · Posted: Wed Oct 07, 2009 9:34 pm Post subject:

_________________
TT Go Essential

	PocketGPS
	Web