Switched 12v source for Boost Gauge

[Paulgo]

Anyone know what wire is the switched 12v in the original radio harness / wiring plug? There's supposed to be a white lead that I think powers the ariel amp under the bee string and would therefore be switched, but not sure if thats right! Also seem to remember something about a red/purple lead being switched 12v??

Fitting a boost gauge and it needs 12v to operate. Easiest option for a non electrician like me would be to tap into the head unit 12v feed as this is very handy to the vents where the gauge will live. Trouble is that this would be a permanent 12v as that’s the way the head unit is wired up at the mo and I’d prefer a switched feed so there’s no battery drain, even tho this would probably be very minimal. The original wiring must be in there somewhere if I can find it! Sorted for illumination as I can use the glove box feed. Tho I think white/blue might be the original feed to the head unit?

Cheers!

Paul

[Jamo]

?

Why dont you simply use the ignition feed on the ISO it will be red or Yellow, can't give you the definitive answer as half the cars i've seen have the colour different!

On my ABY it's yellow (or is it orange)

Yes the white blue wire is the illumination.

[mcandmar]

Is the 12v feed only to light up the gauge? I would wire it into the instrument illumination circuit. Its a big yellow multi connector, have a read here http://www.s2forum.com/forum/showthr...t=heated+seats for a pic of it.

[Paulgo]

Why dont you simply use the ignition feed on the ISO it will be red or Yellow, can't give you the definitive answer as half the cars i've seen have the colour different

Problem is that there only seems to be a single permanent feed into the ISO block with the yellow and red wires then joined on the ISO connection to the head unit I noticed this when I fitted the head unit, tho this actually suits me as I dont like the head unit to go off with the ignition. Gawd knows wots happened to the original wiring / block - its probably there somewhere, but there's been some imaginative work done back there in the past!

Is the 12v feed only to light up the gauge? I would wire it into the instrument illumination circuit. Its a big yellow multi connector, have a read here http://www.s2forum.com/forum/showthr...t=heated+seats for a pic of it.

cheers - that looks like the same connector Jas told me about but I wasnt sure where it lived as its a right tangle under there - so thats useful!! But it needs 12v to operate, so its not just for illumination, although if this block is what illuminates the dash switches doesnt that come on with the ignition rather than lights - in which case it'd be ok?

cheers

Paul

[mcandmar]

Yes its switched with the ignition key, all the dash buttons and elecy window switches are connected to it. I think they stay on as long as the key is in the ignition, i.e. you can have ignition off and they stay lit up until you remove the key.

[Skull]

damn. you really search for troubles. find any black/blue wire and connect to it and go drink a beer. u can take it from the aux gauges, from the witches in the middle console (foglights and stuff)...

[Paulgo]

Yes its switched with the ignition key, all the dash buttons and elecy window switches are connected to it. I think they stay on as long as the key is in the ignition, i.e. you can have ignition off and they stay lit up until you remove the key.

That sounds promising then! How did you hook up to this – can you get a spade connector in the yellow block or do I need to splice into the wires that come out of it? (just to save me time with me head under the dash and legs stuck out on the pouring rain!)

cheers

Paul

[Greg_S]

you could take the feed into the voltage gauge in the dash?

[Skull]

can anybody read my posts? this gauge should be already working a week ago.

[Greg_S]

yeah can see your posts fine

[mcandmar]

Its got nine spade connections on it, most of them are free so just plug a female spade connector in AFAIK the aux gauges are on the same circuit as the main gauges with the dimmer.

[Paulgo]

damn. you really search for troubles. find any black/blue wire and connect to it and go drink a beer. u can take it from the aux gauges, from the witches in the middle console (foglights and stuff)...

cheers! Sorry - just spotted your reply Thats great - just what I needed - now I know what to look for!!

cheers!

Its got nine spade connections on it, most of them are free so just plug a female spade connector in AFAIK the aux gauges are on the same circuit as the main gauges with the dimmer

thanks - if I cant see an easy to find black & blue wire in the wiring behind the head unit then I'll use this!

thanks guys!

Paul

[S4 CRUISER]

elo evryone.sum people really do make life hard dnt they. why dnt u get a multimeter or a test light for a start. then wat u do is probe the wires behind the stereo and look for 12v wen u swith the lights on.its called the illumination wire. simple!!

[Paulgo]

elo evryone.sum people really do make life hard dnt they. why dnt u get a multimeter or a test light for a start. then wat u do is probe the wires behind the stereo and look for 12v wen u swith the lights on.its called the illumination wire. simple!!

As I explained at the beginning of the post - I didnt have a problem finding the illumination wire - glove box feed is simple enough even for me! As I dont have a multimeter I thought the simplest thing to do was identify the switched 12v in the original radio harness if I could - as its been messed with over time (and isnt easy to trace) which I now know to be a blue / black wire

Ask the experts - get the answers you need = no digging about probing a plateful of spaghetti behind the head unit with a torch bulb - to me that's simple!!

cheers

Paul