Astra Mk3 radio wiring - David Horn
Just been putting a new radio in my sister's Mk3 Astra, only to discover that the prat that owned the car before her had been too lazy to buy a wiring adaptor and instead hacked his way through all the wires at the back of the harness, splicing together the ones he needed.

However, none of the colours correspond to standard radio wiring colours, and we can't find the 12V feed from the ignition. There are only two wires in the bunch that look capable of carrying sufficient current, and they're the ground (brown? WHY?!) and permanent live (red).

Not only that, he's hacked off at the base the wires that drive the external display, so we haven't got a hope of ever getting that to work with a Vauxhall radio. Thankfully we bought a cheap aftermarket one.

Does anyone have a guide showing what each colour corresponds to? Desperately needed, as we have no idea where the 12V feed from the ignition is. Previous owner simply put a 25A fuse in the permanent live and spliced the two wires together so the radio had permanent power.

ALSO - don't know if this should be in another thread - the 1.7TD engine has an irritating whine. Is this common with all Astra turbo-diesels of this vintage?


Astra Mk3 radio wiring - Number_Cruncher
I forget the wiring colours, but;

there should be a feed from the sidelights - grey/green?

the ignition feed will not be a large wire, because it doesn't actually supply any significant power - it's more of a signal wire

to find the wiring colours for the speakers, have a nosy at the wiring for the rear speakers, you should be able to see the wiring colours, and then the wiring colours for the fronts should be obvious.

there will also be a wire for the electric aerial - can't remember the colours - sorry!

I hope that's helpful,

Astra Mk3 radio wiring - David Horn
Thanks Number Cruncher - we've taken a closer look and unfortunately there are no other wires carrying a 12V from the ignition switch, so either the switch is broken or the idiot has cut the wire off at the case of the harness out of sight. He's caused unbelievable damage to the wiring harness for the sake of a ten pound adaptor. If I saw him now I could quite happily lamp him one in the face.

New radio doesn't use the feed from the lights, and there's no electric aerial, but thanks for those, the lights one allowed us to eliminate a wire. :) All speakers are working now, but unfortunately the radio doesn't switch on and off with the ignition.

Provided the current draw on the 12V switched isn't that high we might just connect it in with the lighting circuit behind the heater controls, which come on with the ignition.
Astra Mk3 radio wiring - bell boy
david horn wroted<<<<<<<<<<<<<<<

>>>>>>>>>> If I saw him now I could quite happily lamp him one in the face.<<<<<<<<<

and if i had a £1 for every car radio that i had to rewire i would have so much money i wouldnt be able to see the tv monitor.................stress is a killer man................its only a car............. :(
make sure you inline fuse the cradio thingy you are fitting by the way in case bared cables are lurking elsewhere
Astra Mk3 radio wiring - David Horn
Nah, you don't need to be stressed for mindless violence. :)

Yep, the radio has inline fuses on both 12V feeds, although I managed to accidentally take out the 25A fuse powering it by forgetting to switch the meter back from the 10A shunt. D'oh. All working now, more or less.

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