Random wiring! m20

Post Tue Jan 26, 2016 11:06 pm

Have a 1990 320 that I put a m20b25 in to but am wondering what these multi plugs and live feed are for, the live feed was previously plugged in to one of the multi plugs but numbnuts here didn't take note when swapping the looms! The solid red wire runs from behind the glove box to the multi plugs attached to the ecu loom.

Any help would be appreciated!

Post Wed Jan 27, 2016 12:14 am

willnz wrote:1st pic, the plugs will only fit into one particular socket in the accessories socket, each socket is unique in shape. Not sure what the red wire going to the middle right is for though?? Does not look like an OEM wire? So cant comment as to where it should go. You will have to trace it and report where it goes to. (possibly to the red wires hanging down in pic 2?

2nd pic- Those 2 plugs are for aircon and auto box so not used in your case. Red wires hanging down again do not look to be part of the OEM wiring loom so who knows? Trace them back..

Thanks for the reply, the red wire hanging down is the same wire going in to the junction box, sorry I wasn't very clear! Yes I agree it doesn't look very original!

Post Wed Jan 27, 2016 12:27 am

Looks like it's plugged into socket F, which is an ignition switched 12 volt supply, via fuse 10.
Plain red indicates and unfused 12 volt permanent live, soi definitely doesn't belong there.
What were you doing anywhere near these wires for an engine swap?

Post Wed Jan 27, 2016 12:37 am

It's strange because the previous owner must have put it there for whatever random reason, makes me wonder what else is messed around!

Yeah I realised after stripping it all out that I could have just used the original loom but just through in the loom attached to the b25 engine seeing as I'd gone that far haha

Think I'm going to launch that red wire in the bin!

Post Wed Jan 27, 2016 10:04 am

brian_s wrote: Yeah I realised after stripping it all out that I could have just used the original loom but just through in the loom attached to the b25 engine seeing as I'd gone that far haha

Facelift B20 and B25 engine looms are identical, but it's still correct that you removed the old loom, even if you reused it with the new engine.
Engine loom should stay attached and be removed with the old engine, and the new engine should be installed complete with engine loom fully attached to it.
The only connection points to the body loom, on a non aircon. and non EH auto. car are the C101 plug next to the fusebox and battery + and - near the front battery tray.