Car/ Electronics advice

Matblack · 21-11-2006, 14:07

I have an idea that I want to carry through and I want to run it by you guys first.

I have a Bluetooth GPS reciever and I want to permanently wire this to my car in such a way that it is always on, even when the ignition is off. The unit requires a mini USB socket provided by a specially wired charger which goes in a cigarette lighter.

In my car the battery is in the boot which is handy because this would be the least obtrusive place for the GPS attached to the underside of the parcelshelf with Velcro.

Oddly there is already lighter socket in the boot but investigation shows that there is a relay AFTER the fuse to it, so I can't rewire it in the fuse box to be permanently on, besides it would mean messing with the existing wiring and possibly messing up my warrenty in the process.

So the idea is this; to wire a cigarrette lighter directly to the battery. I would fit a fuse inline with the positive terminal so any short would blow it and put some shrouded quick release connections after the fuse so that the lighter socket can be removed easily. I can then plug the charger into this socket and run the cable to the GPS.

Can anyone see a flaw in this plan?

MB

Grandad · 21-11-2006, 14:13

sounds fine

Burble · 21-11-2006, 14:19

I did the same thing for a friend a few weeks ago on her 3 series. Worked like a charm.

kaiowas · 21-11-2006, 14:23

If it's being hard wired I'd probably go without the cigarette lighter connectors altogether unless you particularly want to leave the charger unmolested.

At one time I actually installed USB port in my Cinq. It was power only but it was good enough for charging my iPod. You might be able to get away with similar and cut out using the charger altogether.

Matblack · 21-11-2006, 14:35

How would you go about regulating the power to make a USB port?

MB

Matblack · 21-11-2006, 14:39

The charger itself is a pain in the bloody arse, Holux took it upon themselves to use a non standard way of wiring the cable and when you plug it into a normal charger whilst the unit is on it switches itself off :/

Apparently the charger which comes with it is wired in such as was as to allow you to use it and charge at the same time but I'm going to have to have a good look for it as I'm not sure where its gone

MB

kaiowas · 21-11-2006, 15:21

Quote:

Originally Posted by Matblack

How would you go about regulating the power to make a USB port?

MB

Simple wiring diagrams are out there for that sort of thing although personally I just tapped it straight into the power supply that the head unit was already using, but then I like to live dangerously

Feek · 21-11-2006, 16:53

I'd plumb straight onto the battery terminals, run a fused cable through into the car and hide it under the front passenger footwell carpet, as far back towards the engine compartment as you can. Terminate it with chocolate blocks.

Strip the charger apart so you lose all the unneeded excess plastic, solder wires in the appropriate place and screw the ends into the chocolate block, the charge will probably be small enough to also hide behind that same piece of carpet.

Then you just need to route the cable out and to wherever the GPS is.

This is exactly the same way I've done it in the Feekmobile, heavy duty fused cable out from the engine compartment to termination points.

Matblack · 21-11-2006, 17:03

OK, I've had a look and found the cable I needed, why they decided to use a proprietry wireing in a mini USB cable I have no idea

.

Anyway I've scouted the car and its a piece of the proverbial to get to the battery, its just under the carpet in the boot

I have thought about striping the charger down and making it more stream lined but because its not a normal one I can replace easily I'm going to keep it intact just incase I want to use it in another car at some point. The parts from Maplin are only £8 and that gives me a permanently on socket which could be used for something else if need be.

The only questions which remain are; a) how to attach some little wires to the bloody great terminals on the battery (I would use those cable taps but the wires coming out are too big and b) what amperage fuses to use

MB

Feek · 21-11-2006, 17:05

If you're only using it for that USB GPS then something like a 500mA would probably be enough - But you may find the charger has one built in anyway, these things often do.

Spade terminals. Solder wires into them and affix to battery. Simple.

21-11-2006, 14:07	#1
Matblack Baby Bore Join Date: Jun 2006 Location: Svalbard Posts: 9,770	Car/ Electronics advice I have an idea that I want to carry through and I want to run it by you guys first. I have a Bluetooth GPS reciever and I want to permanently wire this to my car in such a way that it is always on, even when the ignition is off. The unit requires a mini USB socket provided by a specially wired charger which goes in a cigarette lighter. In my car the battery is in the boot which is handy because this would be the least obtrusive place for the GPS attached to the underside of the parcelshelf with Velcro. Oddly there is already lighter socket in the boot but investigation shows that there is a relay AFTER the fuse to it, so I can't rewire it in the fuse box to be permanently on, besides it would mean messing with the existing wiring and possibly messing up my warrenty in the process. So the idea is this; to wire a cigarrette lighter directly to the battery. I would fit a fuse inline with the positive terminal so any short would blow it and put some shrouded quick release connections after the fuse so that the lighter socket can be removed easily. I can then plug the charger into this socket and run the cable to the GPS. Can anyone see a flaw in this plan? MB __________________ "we had roots that grew towards each other underground, and when all the pretty blossom had fallen from our branches we found that we were one tree and not two"

21-11-2006, 14:23	#4
kaiowas The Stig Join Date: Jul 2006 Location: Fightertown USA Posts: 1,458	If it's being hard wired I'd probably go without the cigarette lighter connectors altogether unless you particularly want to leave the charger unmolested. At one time I actually installed USB port in my Cinq. It was power only but it was good enough for charging my iPod. You might be able to get away with similar and cut out using the charger altogether. __________________ Anal Fish Porn

21-11-2006, 14:35	#5
Matblack Baby Bore Join Date: Jun 2006 Location: Svalbard Posts: 9,770	How would you go about regulating the power to make a USB port? MB __________________ "we had roots that grew towards each other underground, and when all the pretty blossom had fallen from our branches we found that we were one tree and not two"

21-11-2006, 14:39	#6
Matblack Baby Bore Join Date: Jun 2006 Location: Svalbard Posts: 9,770	The charger itself is a pain in the bloody arse, Holux took it upon themselves to use a non standard way of wiring the cable and when you plug it into a normal charger whilst the unit is on it switches itself off :/ Apparently the charger which comes with it is wired in such as was as to allow you to use it and charge at the same time but I'm going to have to have a good look for it as I'm not sure where its gone MB __________________ "we had roots that grew towards each other underground, and when all the pretty blossom had fallen from our branches we found that we were one tree and not two"

21-11-2006, 16:53	#8
Feek ex SAS Join Date: Jun 2006 Location: JO01ou Posts: 10,062	I'd plumb straight onto the battery terminals, run a fused cable through into the car and hide it under the front passenger footwell carpet, as far back towards the engine compartment as you can. Terminate it with chocolate blocks. Strip the charger apart so you lose all the unneeded excess plastic, solder wires in the appropriate place and screw the ends into the chocolate block, the charge will probably be small enough to also hide behind that same piece of carpet. Then you just need to route the cable out and to wherever the GPS is. This is exactly the same way I've done it in the Feekmobile, heavy duty fused cable out from the engine compartment to termination points. __________________

21-11-2006, 14:13	#2
Grandad Old Git Join Date: Nov 2006 Posts: 2,016	sounds fine

21-11-2006, 14:19	#3
Burble Rocket Fuel Join Date: Jul 2006 Posts: 7,826	I did the same thing for a friend a few weeks ago on her 3 series. Worked like a charm.

21-11-2006, 17:03	#9
Matblack Baby Bore Join Date: Jun 2006 Location: Svalbard Posts: 9,770	OK, I've had a look and found the cable I needed, why they decided to use a proprietry wireing in a mini USB cable I have no idea . Anyway I've scouted the car and its a piece of the proverbial to get to the battery, its just under the carpet in the boot I have thought about striping the charger down and making it more stream lined but because its not a normal one I can replace easily I'm going to keep it intact just incase I want to use it in another car at some point. The parts from Maplin are only £8 and that gives me a permanently on socket which could be used for something else if need be. The only questions which remain are; a) how to attach some little wires to the bloody great terminals on the battery (I would use those cable taps but the wires coming out are too big and b) what amperage fuses to use MB __________________ "we had roots that grew towards each other underground, and when all the pretty blossom had fallen from our branches we found that we were one tree and not two"

21-11-2006, 17:05	#10
Feek ex SAS Join Date: Jun 2006 Location: JO01ou Posts: 10,062	If you're only using it for that USB GPS then something like a 500mA would probably be enough - But you may find the charger has one built in anyway, these things often do. Spade terminals. Solder wires into them and affix to battery. Simple. __________________