Two Head Units

[Eeyore]

Ello! ive just bought a kenwood screen from a member on here. It was fairly cheap so thought id give it a go. Gutted that a better one sold on ebay for cheaper than what i paid!

Ill be mounting the normal head unit in the lower centre section as that is the easiest place for it and the flip screen will be in the normal radio place.

1. How can I power them both?
Can I plug the loom into flip screen and then splice a power and ground from that and into the loom of the lower head unit?

2. How can I run both through the speakers?
After talking to Niall im pretty sure I cant just splice two looms together as two sources will mess everything up. So my current theory is to connect the pre out of the lower head unit into on of the AV INs on the back of the screen? Then I should be able to play it through the other head unit but adjust the volume on both?

Cheers for anyone who can help! I cant see why the above wouldnt work but i wanted to get some opinions and advice. Of course the real way to do it would just to buy a proper flip screen head unit but they are about £300+ so for less than half of that I thought id give this a go!

Plan is to have a reversing camera fitted too as I cant park the estate and to put in a games console. I did this before but the screen I was using broke before I ever finished

Old pics!

[Tom]

Why do you need both if they're both headunits?

[Eeyore]

oh sorry. The screen is just a screen! it has FM and can play from an ipod or iphone (which i dont have). It has no CD or USB playing capabilities! Which sucks balls! To get flip screens with that you have to pay £300+ which im trying to avoid! For Kenwoods anyway! Both head units are kenwood and I could bring myself to buy a Ripspeed unit for £40 :p

[Tom]

So if the top one is just a headunit surely the only wires you having coming out are just your normal power and speaker wires? If thats the case then joining the 2 is waaaaaaaaaaaay beyond me :/

[Eeyore]

the normal head unit will be built into the lower centre console section. probably where you keep your cds and the flip screen goes where the headunit is meant to go in the silver dash below the vents!

I should only need power wires for the lower head unit as audio is sent via the preout to the screen which then sends it through the standard loom to the speakers!

[aaron_one]

I would also like to know this, i just want to power 2 head units for the novelty effect

[Tom]

Well if thats the case power is a piece of cake!

[Scott]

Wait a sec, if it has ipod/iphone capability then it must have USB input, or a 3.5mm jack?

[DanWY]

Someone correct me if I am wrong but wouldn't it be possible to connect the loom to the top one(screen unit) and then tap into this loom for the switched live and ground needed to power the lower unit (head unit + cd player) as I am under the understanding that this one will just be a slave for the screen unit and sound will go via the pre out's etc.

[Tom]

Someone correct me if I am wrong but wouldn't it be possible to connect the loom to the top one(screen unit) and then tap into this loom for the switched live and ground needed to power the lower unit (head unit + cd player) as I am under the understanding that this one will just be a slave for the screen unit and sound will go via the pre out's etc.

Thats how i'd do it, then if you start blowing fuses you'd have to look into other methods

[Niall]

Someone correct me if I am wrong but wouldn't it be possible to connect the loom to the top one(screen unit) and then tap into this loom for the switched live and ground needed to power the lower unit (head unit + cd player) as I am under the understanding that this one will just be a slave for the screen unit and sound will go via the pre out's etc.

Thats how i'd do it, then if you start blowing fuses you'd have to look into other methods

Haha i do love how pikey some people can be with electrics!

With regards to power, i would T off of the original loom and then work out your total current draw and replace the fuse to suit providing it isnt that big a jump otherwise the wiring will have to be upped. Luckily, they normally over compensated for wire size anyway!

Dont be under the impression either that you can just mash wires together and worst case is it will blow a fuse. Not everything is fused and you can do a lot more damage than just a fuse!

[Eeyore]

Someone correct me if I am wrong but wouldn't it be possible to connect the loom to the top one(screen unit) and then tap into this loom for the switched live and ground needed to power the lower unit (head unit + cd player) as I am under the understanding that this one will just be a slave for the screen unit and sound will go via the pre out's etc.

yeh thats the plan. But then can I put a cable straight from the preout of the headunit to the AV of the screen or is it too much for it?

Maybe the fuse for the radio will have to be upped a bit in order to power two of them :/

[DanWY]

I would do as Niall says you need to work out the load etc for the wire, I would also personally put a fuse inline on the power wire between the two units. I'm not 100% up on the electrics of the car etc so maybe someone who knows more about the wiring would be able to advise on that but I can't see a problem with wiring two in the way I said apart from checking the current draw to make sure it's not going to start melting the cable.

I know when I wired some lights in my previous car I went ott with the cable to make sure it didn't melt, I used 20a cable for LEDs possibly only drawing a couple of amps.

[cully]

sam on my system
i run two head units
12+,grnd,aerial are spliced
but
the second head unit uses the first as the master for the speakers

so speaker outputs on the second head run into a Line Output Connector (Halfords Autoleads PC1-601 Line Output Connector £7.99) this drops the signals down so i can use the line in on the 1st head unit, which then uses the existing speaker system

[Eeyore]

sorted. Exactly what i was looking for. Cheers Cully! Ill probably have this bad boy all sorted in a few months time!

[Kwik]

i would splice the 12v ignition but i would run a new ground and 12v constant. is not that hard and a hell of alot safer. make sure to fuse the new 12v constant and you would want a cable capable of 20-30amp constant loads (maplin sell a high current lead xm57-59 iirc) if the screen has a fm only need one aerial lead

The pre outs will work fine on the other head unit and if possible on it turn off the internal amps on the cd HU which will give you a boost in audio quality out the pre outs and make it run less hot