318i ICE (head unit & speakers) install help

Post Sun Aug 02, 2020 9:21 pm

Hi,

I've recently bought a 318i touring and am looking at fitting a new bluetooth capable head unit and speakers. I've seen the guide on the wiki but understand that some E30s have different wiring colour schemes– I was hoping to find a guide specific to my vehicle before I get underway with the installation.

The car already has an aftermarket JVC head unit which I've taken out in an attempted install previously, but found that the plug it uses doesn't exactly match the one supplied with the Sony head unit I'm looking at using. From what I understand, it should be a matter of identifying the individual wires in the car, trimming them and then crimping them to the wires attached to the Sony plug. However, I'd like some more guidance on which wires are which before I go in and possibly break something.

Regarding the speakers, there is only sound coming from the left hand side of the car. I'm hoping this would be solved by installing new speakers, but was wondering how I could check to see there's not an issue with the wiring which handles the right side of the car before I install new speakers and find out they don't work.

I'd appreciate it if anyone could either give me a list of which wires serve which purpose or point me towards some resources which can help with the install. I can provide photographs of the current situation with the head unit wiring.

Thanks

Post Sun Aug 02, 2020 9:46 pm

Send in some pictures, hopefully you have an ISO harness already. The colours are all standard now so your current head unit harness may well be wired to this. Regarding speaker output I presume you have tried the fader and balance? If they are both set to extreme you will only get sound from 1 speaker as one does left and right the other front to rear. Try this before just buying speakers.
There are also many adapters available from one type of harness to another but obviously it would be undesirable to have more than one in line.

Post Mon Aug 03, 2020 7:16 am

Yeah, I've just taken it out and looked again and there is already an ISO harness which is incompatible with my new headunit. The wires lead into the loom and are wrapped with cloth, I'm assuming this means this is the stock harness which came with the car? Also, regarding the speakers; I had a play with the balance and found that only the front left and back right speakers work, which is interesting. I'm assuming then it must be a localized problem with the speakers?

I've attached an image of the harness, there are some wires there which just terminate and aren't attached to anything, I'm not sure what these do?

Thanks for the help.

Screenshot_20200803-071016.png

Post Mon Aug 03, 2020 8:20 am

You could remove the speakers that work and connect them at the non working speaker location and see if they work that side. If they do you know the wiring is good

Post Mon Aug 03, 2020 8:26 am

chatstar123 wrote: ↑
Mon Aug 03, 2020 8:20 am
You could remove the speakers that work and connect them at the non working speaker location and see if they work that side. If they do you know the wiring is good

Thanks, no idea why it didn't occur to me I could do this before going out and buying new ones lol.

Post Mon Aug 03, 2020 4:41 pm

I would personally re wire to get rid of the chock blocks as these are generally considered a bodge but leave an ISO connector on the car side and then use whichever harness you need to go from this to your head unit.
This way it future proofs the wiring on the car. That's the way mine was done by a PO and the Blaupunkt Bremen connected straight up as it uses ISO. The wiki mentions standard BMW wiring, a quick Google brings up plenty of colour diagrams.
Speaker wise you could try as suggested or get the head unit connected but outside the dash and test with the new one.

Post Mon Aug 03, 2020 9:37 pm

Dlb26 wrote: ↑
Mon Aug 03, 2020 4:41 pm
I would personally re wire to get rid of the chock blocks as these are generally considered a bodge but leave an ISO connector on the car side and then use whichever harness you need to go from this to your head unit.
This way it future proofs the wiring on the car. That's the way mine was done by a PO and the Blaupunkt Bremen connected straight up as it uses ISO. The wiki mentions standard BMW wiring, a quick Google brings up plenty of colour diagrams.
Speaker wise you could try as suggested or get the head unit connected but outside the dash and test with the new one.

Thanks for the advice, this is what I ended up doing. Got my head unit and and ISO connector from Halfords and ended up just swapping whatever harness the JVC was using for an ISO one which the Sony then went into.

Luckily, I found out that the speakers were non functioning because some of the +/- wires had come out of the blocks. I ended up just using them again but intend to go back and solder in the ISO since by following the way it was wired previously I managed to swap the left and right sides. Also in the excitement of getting the unit in I think I crammed the wires too hard and disconnected one of the speakers immediately.

Overall, I'm chuffed with how it turned out. In retrospect it seems like such a simple process but it took me a couple hours to work out what I was doing.

Here's a shitty flash photo of how it ended up.

Screenshot_20200803-213633.png