Before I install my new head unit, can someone please advise....

[darkhorse1210]

On whether I've got the wiring correct here on the picture.

It's an Alpine 9855 head unit which was brand new and boxed so the wiring was never connected.

I've simply joined the reds together and the yellows together and zip tied the connectors I don't need (dimmer, bluetooth cut out etc).

Before I go and try and install can someone please confirm this is correct?

Thanks

[quattro-nick]

the yellow wire needs constant + (battery+30) for memory and the redwire needs + after contact(+15)
black is ground -(31)

[darkhorse1210]

the yellow wire needs constant + (battery+30) for memory and the redwire needs + after contact(+15)
black is ground -(31)

Nick

I'm a total amateur at car stereo installs, I'm not that sure what you mean there.

Based on my picture have I connected the wiring correctly or incorrectly??

[quattro-nick]

it depends on the car
what i mean is,yellow needs all times power,red needs power after you put your contact on(key turned)
you can check it like this: plug your radio on,set your contact on,radio must play,if it play,set radio on a good station
set your contact off and wait 5 min.turned contact back on and radio must play on the same station as before
if the radiostation is lost,swith the red wire with yellow

[Error404]

You may need to run a switched +12v as there is not one in the OEM ISO plug.
You can take this from a few places, the dash switches, aux gauges or ignition switch are closest

[darkhorse1210]

it depends on the car
what i mean is,yellow needs all times power,red needs power after you put your contact on(key turned)
you can check it like this: plug your radio on,set your contact on,radio must play,if it play,set radio on a good station
set your contact off and wait 5 min.turned contact back on and radio must play on the same station as before
if the radiostation is lost,swith the red wire with yellow

OK, thanks, I'll check this out in the morning and post back.

Ta

[newsh]

On the back of the ignition switch there's a thin red wire, the good thing about this wire is that it comes on with the ignition but stays on when you switch off untill the key is removed, means you can listen when parked up. You always have to switch on to power up but then you can switch off and leave the key in.

You need to tap into this wire, strip a little bit of the insulation off so the copper is bare and wrap a wire around this, solder it if you have an iron or wrap tightly with elec tape if not. Run this wire to the back of the stereo making sure it's not going to get caught up in the steering column or pedals and not going down the back of the heater controls. Look at the ISO plug that has the red and yellow wires, you'll find the red one has no pin on the car side, that's where you need to connect the thin red one. If you don't have a spare pin then you'll need to splice it to the stereo loomlooks like you have a fork on the red wire so you could connect to that. As above, if you switch off and it loses it's memory then you need to reverse the red and yellow connections.

[rj scotty]

Just a word of warning; Alpine head units a a fooker for draining batteries. You must run a switched live to an Alpine head unit IMHO.

[darkhorse1210]

Cheers for all the advice on this one.

It turns out I had the wires the wrong way round, plus there was an ignition feed wire(?) that had been wired in on a previous install so that made things a lot simpler.

A mate of mine wired it up and it works lovely.

In terms of sound quality this is the best sounding head unit/speaker combination I've had so far and I've had plenty. New Focal speakers front (CA1s) and rear (Focal Performance) finished this off. The Alpine might be old now but it really is a sweet sounding head unit. They can be picked up cheap(ish) on EBay too so worth a look. You can even run the IPod through a KCA-420i which sits lovely in the cavity below where the head unit fits into the dash (i.e. behind the heater/blower controls.

You don't get the red illumination of the Becker Grand Prix but other than that you'd be hard pushed to find something better for the cash....

[newsh]

Nice one

[Ironman80]

According to this scheme, the HU will operate after the ignition is turned off before turning off the device. The next time you can turn on only after ignition. And the battery is not discharged.

[ujimaflip]

How should I run a wire from the ignition switch?

On the back of the ignition switch there's a thin red wire, the good thing about this wire is that it comes on with the ignition but stays on when you switch off untill the key is removed, means you can listen when parked up. You always have to switch on to power up but then you can switch off and leave the key in.

You need to tap into this wire, strip a little bit of the insulation off so the copper is bare and wrap a wire around this, solder it if you have an iron or wrap tightly with elec tape if not. Run this wire to the back of the stereo making sure it's not going to get caught up in the steering column or pedals and not going down the back of the heater controls. Look at the ISO plug that has the red and yellow wires, you'll find the red one has no pin on the car side, that's where you need to connect the thin red one. If you don't have a spare pin then you'll need to splice it to the stereo loomlooks like you have a fork on the red wire so you could connect to that. As above, if you switch off and it loses it's memory then you need to reverse the red and yellow connections.

I've seen a few threads suggesting running a wire from the ignition switch to the radio. I found that my radio has the red and yellow taped together - perhaps one of the reasons that my battery drains so rapidly... So I thought I would have a go. I have the dash out - I took a picture of the switch:



What the best way to get the switch out without breaking anything (I'm a little nervous )? If I'm successful I'll post more pics for others to follow.

[UrS4boy]

C4 Ignition Switch Replacement DIY pdf

Read through this C4 ignition switch replacement DIY (the switch and the procedure will be 99% the same as a B3/B4):

http://12v.org/urs/IgnitionSwitchReplacementDIY.pdf

[ujimaflip]

Which wire should I run the ignition from?

I pulled the connector off - this is what I see:



Which of these is the 'small red wire'. Any help gratefully received

Dan

[UrS4boy]

Annoitated RS2 ignition switch wiring

Which of these is the 'small red wire'. Any help gratefully received. Dan

I previously researched and annotated this RS2 ignition switch diagram for someone here on the S2Forum. One of the responses was the "86S" is what they use to provide power to their radios (I presumed they meant aftermarket). If you did that, you'd want to install a fuse between the 86S and the powered device because the igniton switch is not fused between the "30" constant power and the ignition switch.

The pin-out info references S2s and RS2s but the principle should be the same:

first "30" = thick red
second "30" = thick red
75 = black/yellow to load reduction relay (during starting)
P = green/yellow
86S = thin red
50 = red/black to J59 X-contact Load Relief Relay (power flows through it to other devices AFTER the engine has started (or at least the switch has been turned to the run position) = could include some circuit fuses like S12.
50b = thin blue
15 = *SWITCHED* POWER thick black that will feed lots of fuses, like S12, etc.