How to connect that new car stereo ?

[cacaolat]

Hi, I have just ordered a new sony car cd player/mp3 and all that stuff....
I may fit it in the next few days. I don't really want to cut off either the cable connectors on the car or the stereo.
I guess I can just use the small cable connectors (sorry don't know how they are called) ...I have read before that it is not always straightforward. How should I solve the issue of switched power connection or unswitched power connection. Do modern stereos really drain the battery ? where is an easy place to get a switched power connection from ? cigarette lighter or something like that ?

[jeremy]

I fitted something similar to my BX but its not a Sony!

I used an ISO converter from Maplins which converted the car to modern wiring and plugged the radio into that. I kept it unswitched and this was no problem when I used the car every day but would run the battery down after about a week or 10 days.

These things can kick out some power and too thin or tortuous wiring may affect sound quality - so ideally take a switched source and use it to feed a relay control circuit then use the existing heavy lead for the power circuit via the relay. I don't think the cigar lighter is switched on Citroens (it is on Renaults as I found out when I tried to run my tent lights off it as I used to do with my Scirrocco) but there may be something suitable powering the heater blower.

Do you have rear speakers? If not your Sony may cut out mysteriously. I later removed my MP3 player and put it in the ZX (which has a switched supply). The ZX has front speakers only and the set needs re-setting occasionally - which I think is due to something being unstable caused by no load on the rear speaker circuit. It never cut out in the BX even with a dud rear speaker - but I have found with domestic amplifiers that just the lead can be enough to prevent fuse blowing with speakers disconnected.

[cacaolat]

thanks for the advice....I hope I will manage to get the connections right....hopefully the instructions with the radio explain about it....
No I don't have rear speakers...I have actually wondered where they are normally fitted ? in the doors ? are the speaker cables already factory fitted ?

[cacaolat]

sorry I have realised that the same issue has already been discussed here http://www.bxclub.co.uk/forum/viewtopic ... t=switched

[cacaolat]

Huh ! have read the other thread....is there no other way ? soldering ! removing centre console !

[Doz]

I made my own ISO converter out of junk bits so I could leave the original wiring in place. My "new" stereo is an Alpine MP3 thing. It's on the unswitched supply and seems fine. I did have a problem with the battery, but now I've changed it I can leave the car for weeks and it still goes second turn of the key!
I changed the front door speakers as well, as on the originals the cones had parted company with the baskets!

All in all a nice set up now. I like being able to have 10 albums on one disc. Yes' entire back catalogue on 3 discs!

[jeremy]

It is not necessary to solder. I like it as it produces a neat reliable joint that won't shake loose. You can use screw in connectors (white plastic things that come on a strip available in the electrical section of B&Q and similar), butt splices (insulated sleeves that are crimped on) or even Scotchlocks for piggybacking onto a wire. What I can say is that the better you do the job the better it'll work and just twisting wires together and taping will probably cause problems.

I connected my ISO connector to the existing wiring with screw on terminals as I wasn't sure I'd got the speaker circuit quite right and also because I couldn't get the soldering iron in the space easily and I didn't fancy more dismantling.

You are looking for a switched feed - I earlier suggested the heater motor supply - but on reflection its not the best as it is in the earth return after passing through a motor and could lead to interference. The clock wiring is easy to get at if you have the one in the tray in the centre of the dash and a connection could be made outside the clock in its supply wires. The only switched supply is however the panel lights which would power a relay control circuit only.

Part of the fun of auto electrics is finding convenient power sources that do what you want them to do and tapping them.

Of course you could put a simple on-off switch in the POWER (NOT memory) circuit so when you leave the car you have to remember to manually turn off the radio supply.

[jeremy]

It is not necessary to solder. I like it as it produces a neat reliable joint that won't shake loose. You can use screw in connectors (white plastic things that come on a strip available in the electrical section of B&Q and similar), butt splices (insulated sleeves that are crimped on) or even Scotchlocks for piggybacking onto a wire. What I can say is that the better you do the job the better it'll work and just twisting wires together and taping will probably cause problems.

I connected my ISO connector to the existing wiring with screw on terminals as I wasn't sure I'd got the speaker circuit quite right and also because I couldn't get the soldering iron in the space easily and I didn't fancy more dismantling.

You are looking for a switched feed - I earlier suggested the heater motor supply - but on reflection its not the best as it is in the earth return after passing through a motor and could lead to interference. The clock wiring is easy to get at if you have the one in the tray in the centre of the dash and a connection could be made outside the clock in its supply wires. The only switched supply is however the panel lights which would power a relay control circuit only. The heater circuits pass through a plug to the control board and this plug is accessible through the clock tray.

Part of the fun of auto electrics is finding convenient power sources that do what you want them to do and tapping them.

Of course you could put a simple on-off switch in the POWER (NOT memory) circuit so when you leave the car you have to remember to manually turn off the radio supply.

[cacaolat]

Thank you I will try it from the clock then (did I get that right ?)
and of course I would just make good cable connections....after a few cable melting experiences years ago i got that one....

[cacaolat]

I did have a problem with the battery, but now I've changed it

Hi Doz...have you changed the battery or the unswitched connection ? if it was the connection did you take the unswitched power from the clock ?

[mat_fenwick]

All the radios I've fitted (about 5 or 6) use the unswitched source as the main power supply, just using the switched supply as a trigger within the head unit itself. However I know this isn't always the case (some use a switched main feed with a low current memory back up supply).

A lot of units have detachable connections on the switched and unswitched supply so you can swap them round - can you find out which type yours is? (If the manual is no help then there may be an inline fuse in the connectors with the head unit, perhaps 10A - that should be the main power feed). I used the existing unswitched supply as the main feed and took a switched supply (and one for the panel lights) from the back of the clock.

[cacaolat]

I am still waiting for the stereo to be delivered to the pick-up-store !! I was hoping to be able to pick it up today, but it was a bargain and has all the mp3, aux input I want...(fed up with radio and tape)....

[cacaolat]

Thank you very much...for all that good advice. I got a multimeter to be sure about the connections and connected the switched supply from the clock (it is the grey cable)....great it all works a treat now....and I don't have to worry about draining the battery