Switched live and interior lighting feeds behind stereo?

[type S]

I'm hunting about for live and switched feeds to supply my defi gauge controller behind the stereo / aircon units.

Does anybody know what the three cables to the cigarette lighter are, i'm assuming live (+12v), earth (-) and interior lighting circuit (switched live)?

Which one is which? <--- Most importantly

And can i take a feed off the interior lighting circuit (switched live) and have it so that the cigarette lighter illumination still works as well (and how)?

Thanks as always.

 

[JaseYpk]

Yes, the cigarette lighter has an "ignition on +" as its where i've got my defi gauge connected to it. but an easier location to 'tee off' for an ignition on, is the back of your stereo. the cables back there are usually labelled up and well colour coded! red or yellow is usually ignition on, with the other people permanent on.
every stereo is different, btu check your harness. it shouldnt be too hard to figure out.

.. just checked some old photos i had, and my defi power cable is going to the RED one on the cigarette lighter

if you intend to use an interior light, make sure you use one which is always on when the ignition is. and not when the door is open or key removed lol

 

[Nickichi]

The only snag with using the cig lighter to provide a switched line sensor is that when you start the car it it is disabled by a relay and is considered part of the acc equipment, the defi book states that it requires a connection to the dedicated "on" switch line from the key. I used the wires feeding the hazard light switch to provide all the feeds I needed but i gotta warn you i think on my car the connections weren't good (or just too long) cause sometimes when I start the car, the defi unit turns off from the drain on the battery from the starter motor although if i half turn the key and hear the relay click it stays on so im guessing the voltage drops too much atm.

i'll dig out the schematic later and post a pic unless someone's got a better way to connect it up

 

[S15 SILVIA]

I sometimes get this problem with my head unit.
Sometimes when I try to start the car, the stereo will reset itself, I then have to enter the pin, and adjust all the speaker settings etc. Does my head in. think its down to the stupid sized battery, and the fact I dont use the car as a daily.

 

[type S]

Prob should've said i haven't got a stereo or the connections so it'd have to come from the cigarette lighter / hazard lights / somewhere else.
I *might* have a switched live already tho.
Thought the cigarette lighter was pretty much always live and any 'dedicated live' was going to have a voltage drop under starting loads anyway?

 

[Nickichi]

think its down to the stupid sized battery, and the fact I dont use the car as a daily

will have to try a larger battery sometime, still got room under my hood


Type S, see attached schematics

the wire feeding from the cig is only a switched live not dedicated from the Batt, i've attached the schematics for the overall system, the cig lighter, the hazard light and the radio connections so you can identify by the colors. take your pick.

would also suggest downloading this http://download.s15oc.com/s15_service_manual.zip i took the file to work and printed it all off after the office was empty, comes in handy if your working on it

on the main schematic the holes symbol in the key switch shows what items are connected depending upon the key position

Hazard Lights



Main schematic



Cig Lighter



Radio

 

[type S]

I think i can work with that! Thanks Nick.