Car Head Unit wiring guide

[glennda]

I'm looking to put some speakers in a car for my little brother along with a new Head unit. This car doesn't have any rear speakers I can splice the audio connection from which is what i did on my previous car (disconnecting the old speakers).

 

What i am proposing to do is detach the speaker connection from the back on the head unit and then run new cabling through the car to the back. My stumbling block is i don't know which cables are the speakers.

 

Is anybody able to shed light on it? The attached are the pictures of the connections in the car. Its an S reg Renault Clio if thats any use to people!

 

[3s-gtech]

Top connector is for speakers. For sound quality, it's always best to keep the front speakers connected - rears are far less necessary. If you're looking at 6x9s on the rear shelf, also bear in mind that fitting them often causes the structure of the shelf to fail with the weight, and they are a very obvious theft magnet.

 

Can you upgrade the fronts instead? Or even better, utilise the rear outputs from the headunit by swapping out the car's white ISO connector for one with four channel output (just a case of cutting it off and joing a new one in). That way you can keep the fronts, and run speaker wire to the rear from the other channels).

[glennda]

What connector would i need to be able to change the output? I was going to cut and splice both front and rears into the same one it would just not be able to be faded back

 

I think the parcel shelf should be ok as its quite a thick one. My old fiesta had thinner and was ok.

[tomgrindle]

I'm not 100% sure but I think you can buy the little connectors to crimp onto the end of wire and then push into the correct place in the block connector to correspond with the stereo.

[newpersn]

I would use the stereo iso. As above can't you upgrade the fronts?

 

What car is it? Looks like its French by that plug

 

Has he got a sub inthe boot?

[glennda]

I would use the stereo iso. As above can't you upgrade the fronts?

 

What car is it? Looks like its French by that plug

 

Has he got a sub inthe boot?

 

No sub its a old S: reg Renault so yes its french!

 

I havn't seen the fronts to be able to check that yes. But i've got some old 6x9's from my old car which i was going to use to save money!

[crc-ict]

What I would do is get hold of the cheapest wiring adaptor I could find that had ISO connectors (the black and white plugs in your pics are ISO connectors), then remove the two outer pairs of connections from the white connector, splice them to new speaker cables and then insert these connections into the car's white ISO connector. Voila, you then have wiring for rear speakers and the car's original wiring is intact.

 

Older Renault's can have debatable wiring so it's best to avoid messing with the car's wiring loom if you can help it.

[3s-gtech]

^^Basically what I would suggest - but I always found it tricky to get a good connection using a two channel speaker connector for the car, which is why I suggest putting in one from a four channel setup. You won't affect the general condition of the electrics by doing this! You cannot run both front and rear speakers from the same two channels from the headunit though as I think you've suggested - you end up running two 4ohm loads in parallel per channel which = 2ohm. Most headunits get very hot and may be destoyed with such a low impedance on the amp.

[crc-ict]

Sorry, yes bit of confusion, I was suggesting adding terminals to the four vacant outer positions on the original car connector to provide the rear speaker feed. The connector allows for front and rear L & R outputs, just the current connector doesn't have the terminal pins fitted.

 

Certainly, don't wire extra speakers to 'piggyback' the front connectors!

[gshaw]

Unless you carry passengers who want to hear the audio I'd upgrade the fronts with a set of components instead as you'll get a more noticeable improvement in sound quality over additional fill from installing rears

[twin--turbo]

dont join them.

 

you will end up with a 2ohm load that the head unit may not be able to handell.

 

as sugeted just find a 4 way plug, run the cable to the rear.

 

I hardly ever keep stock wiring when I am upgrading.

 

rob

[newpersn]

U need one of these

[glennda]

U need one of these

 

it's blank?

[oxide54]

halfrauds do a lot of iso adapters