Connect LCD directly to car power supply

**demc7** · 10-02-2006, 07:25 PM

Recently decided to set up a simple car pc system. The components will only be a Lilliput screen and a laptop. My only questions are as follows:

As it stands, I will have two plugs going into the cigarette lighter, for the screen and laptop. This is bad, extension cables etc. So I was wondering if it is normal to connect these into the wiring loom behind the cigarette lighter. I imagine it is... all I do is strip the wires and connect them directly to the wires going into the lighter? Should this work?

The lighter and the car heater are connected to the one 30a fuse. I won't use the heater so should 30a be enough for my setup?

Thanks everybody.

-> Just one quick comment, don't want to start a new thread, is connecting this system to a standard tape deck advisable? Or is that the number one sin in car computing? Thanks guys. And if anybody has any tips how to connect an aux-in wire to a 97 Fiat/grundig stereo (via the cd changer control, mini iso) you will be my friend for life. I have tried but the stereo won't recognise the wire (think i need some voltage across it for the stereo to notice it, whats going on?)

**pate60** · 10-02-2006, 07:52 PM

hi,

that sounds a bit strange to me that, a cig ligther would have a 30A fuse, normally they are fused separetly anyway, i doubt that you'll even get close 10A for caputer.

i dunno anything about that system, simple way is to use a digital fm modulator.

**mgithens** · 10-02-2006, 10:02 PM

the screen is usually 1A (12 watts) and the typical laptop power supply is probably less than 150watts, so 10 or 12 amps... this is a bad idea, get a good wire (10ga is enough) and run it from the battery... please, please, please fuse protect this...

the AUX in is the best plan, on the tape deck idea if you were talking about one of those tapes with the cord hanging out... NO... :-) don't do it... cords look bad, tape decks sound bad... FM modulators are worse, go the extra distance and get the AUX in working... probably need to search for some forums for your car... this battle has most surely been fought and won... you just need to hunt down the victors!!

**pate60** · 10-03-2006, 09:15 AM

digital ones that dont drift are fine!

**mgithens** · 10-03-2006, 12:37 PM

the heater draws very little current, I bet it is a couple amps at best... all the "heater" is just a fan...

**demc7** · 10-03-2006, 03:30 PM

A 10ga wire... I dunno but does that mean 10 giga-watts? like 10,000,000,000 watts? My units must be wrong.

Getting a workshop manual for the car ('97 Fiat Marea....I'm in Ireland, hence European car) so that should fix the problem of connecting an aux to the oem headunit cd-changer socket.

Question: Looked up DC-DC converters, they are only a few dollars, and you connect them into the cigarette lighter. Is this right? So is it safe to connect the two wires from the laptop and lcd together so I only need one cigarette socket? still thinking i might be able to connect them into the wiring behind the lighter, bypass the lighter, does anybody do this?

Thanks guys

**Wiredwrx** · 10-03-2006, 04:34 PM

Originally Posted by demc7

A 10ga wire... I dunno but does that mean 10 giga-watts? like 10,000,000,000 watts? My units must be wrong.

Getting a workshop manual for the car ('97 Fiat Marea....I'm in Ireland, hence European car) so that should fix the problem of connecting an aux to the oem headunit cd-changer socket.

Question: Looked up DC-DC converters, they are only a few dollars, and you connect them into the cigarette lighter. Is this right? So is it safe to connect the two wires from the laptop and lcd together so I only need one cigarette socket? still thinking i might be able to connect them into the wiring behind the lighter, bypass the lighter, does anybody do this?

Thanks guys

10ga means "10 gauge", it is a measure of diameter of the conductive component of the wire.

Michael

**demc7** · 10-03-2006, 04:48 PM

Cheers. 10 giga amps is pretty funny.
Would that be easy, running a wire from the battery? The most dismantling I am prepared to do with this car is removing the centre console, I'll try my best to get around it another way, if I need to do major dismantling.

Workshop manual I've ordered should show me any unused wiring for a/c or things like that (which I dont have).

**mgithens** · 10-03-2006, 06:23 PM

using the factory wiring is generally frowned upon... going straight to the battery is really easy, pay an installer to put the wire in place for you... probably cost ya $20USD in labor...

you sound like this is beyond your normal scope, do not let fear keep you from doing it right... I advise that you DO NOT run it off the cigarette lighter...

**demc7** · 10-04-2006, 06:09 AM

possible to run it from anywhere in the fuse box, the battery seems a bit of a distance. And if it was coming from the battery, would it be connected right to the battery itself?

Might just get somebody to do that bit, good advice.