I want to hide my tomtom car charger

Jun 10, 2009
Ok Ive been at my dad to hide my tomtom car charger for weeks now. He finally went out to do it tonight to find that the charger is 5v and cars have a 12v supply. He cut off the end bit of the adaptor to find three wires instead of two. He was suprised as he is an electrician. I think he said that the third was to stop it from charging when fully charged, Im not sure.

Anyway he has told me to look for some type of 5v to 12v converter. Can anyone direct me to what Im looking for.

Just to verify what Im trying to do. I want the charger to be wired to my tomtom then to feed it through the car to a power supply so that its charging and its completely hidden and also frees up the cigarette socket.

I told him just to wire it anyway, he said dont be stupid as it would blow it. Is this true, he thinks hes right everytime and Id just like to prove him wrong for once....lol
In the plug that you have chopped off is the voltage regulation circuitry needed to convert the 12V to 5V, if you connect a TomTom dirrectly to +12V it will emit rather costly smoke so DON'T DO THIS

You need to purchase another ciggy lighter socket and wire that to the cars 12V electrical supply, insert the TomTom charger lead to this and bind with tape to secure the unit and stop it falling out, route the cable through the back of the dash and you will have a neat installation, I did something rather similar over the last weekend with some of my kit, perhaps this might help as a guide:

I decided I had seen enough of all those cables strewn about the car and decided to tidy it all up - Far from a small task due to the amount of wiring from the new stereo that seems to have apeared since the first post:

Having removed the central air vent from the car I set to with a Dremel to cut a small access hole for the cables that were going to the 940, in this case the power lead, audio line out and the RDS-TMC round style plug

The three cables are easily fed through the newly made hole, any V70 owners should note the area I cut through is doubled skinned so you need to make two cuts and if you remove the Climatic Control Panel do not disconnect it or the car will throw an airbag fault.

Feeding the cables through the airvent was good fun, in the end I took the vent to bits and put the cables through where I needed them before reassembling the vent afterwards, fiddly but not impossible, the trick is to only put the power cable through one opening and the othe other two cables through an adjacent vent hole. Doing this lets the airvent still operate correctly and spreads the cables ready to connect to the 940 mount.

As I had most of the dash trim out of the car for access and I hate wires in the car I decided to sort out the iPhone cables at the same time, the power connector for the iPhone is easily removed from the Brodit holder by releasing the two screws on the rear of the phone holder, this makes it much easier to push the cable with connector through any available gaps in the trim.

Push the connector back in to position within the Brodit mount then resecure using the closure plate and two screws.

Resecure the Brodit Active holder to the swivel coupling by tightening the center screw, only finger tight is needed though, any more than this will snap the plastic on one part of the ball joint.

I pulled out the stereo to gain access to certain connections, firstly the RDS-TMC receiver needed connecting to the car aerial cable via a splitter cable I made a while ago (detailed in This Thread).

I was also fitting a three way 12V outlet socket to power the TomTom charger and iPhone power addaptor, the feeded wires to this were simply tagged to the stereo ignition switched power wires using Scotch locks.

At this point its worth checking the power is working correctly so I switched it all on and got indications of charge for both the 940 and the iPhone so it was time to start tidying up.

Before burying all of this I taped up the power addaptors so they couldn't migrate out of the sockets due to vibration and/ or thermal creep - easy to do just bind them together with PVC tape.

The power addaptor was then secured to the underside of the glovebox support bracket with more tape, it looks a little unsightly but once the cars back together non of this will be seen. The orange boxes are part of the iO-Play device I added to the car for decent Handsfree support, this is detailed in This Thread, the boxes get hidden when the trim is replaced.

I added a new cable to the stereo during this install which adds iPOD support to the stereo, whilst I probably don't need this (yet) it saves taking the whole lot out again to add a simple cable, this is nothing to do with the TomTom but adds iPOD input to the stereo and offers full control of a device plugged in to it. I decided against using this with the iPhone as I have a Bluetooth module for that which negates the need for cables.

All cabled up and working - Oh look no wires and remember this includes an RDS-TMC receiver, much neater even though it did take a few hours.

With the 940 off its bracket all that is left is a simple shoe that is pre-wired and ready to go once the device is dropped in to position.

The iPhone holder also attracts less attention as there are no tell tale wires going to it strewn all over the car.

Next job is to vac out the inside of the car, bits of black plastic dust have got all over from the cutting job, but overall I am happy with the installation and the flexibility I get from the kit - Mike
Nice job, thanks for the advice. Whats the mount you have for your tomtom, its not like the air vent mount Ive seen tomtom selling.
Mike made reference in a few of his photos to a Brodit Active mount.

A link to a detailed review of the mount can be found here

It's from pocketgpsworld.com (also) in the UK, where Mike is a moderator.

So you should find outlets for the product there.
The 940 mount pictured earlier is sold by TomTom see Here to use it you also need a Brodit Pro-Clip to suit your car (lots of choices are available for most cars). Note this mount will only accept the x40 TomTom units, if you have an x20/ x30 unit then the link David offered shows you a similar third party mount for these units - Mike
I didnt actually understand your post Mike. Im just presuming my dad will when he comes around. I'd rather you explain it to me a bit further so if I need to get anything for him I can before the shops shut.

Ok so I need to cut off the socket of the car charger then Ive got red, black and white wires. So what do I need to connect to them so I can connect it to the car electrics.

I read somewhere its an in line converter, that will convert the 5v.
You need to put the TomTom supplied charger cable back together, make sure all three wires are correctly soldered and innsulated from each other, if the third wire breakes it will fry you device.

Once the existing charger cable is repaired you need to insert this in to a new ciggy socket that you locate behind the dash, this is wired to the cars 12V supply via a fuse and its best if the supply is switched via the ignition key (Pictures 7 to 11 in the previous post show this) - I am sure your dad will realise having read through all of this that the TomTom supplied charger lead contains the voltage regulation circuits and MUST be used, chopping the plug of this will not work - Mike

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