c101 and x20 wire diagram (e30 M50 adapter)

[FredK]

Thanks!

Sorry to hear about your track mishap. It sounds like you have a pretty sweet replacement lined up!

[Bimmer335is]

'87 c101 connection to s50 wiring harness

I read through the entire 50 or so page swap thread and found nothing helpful for me with s50 wiring in an '87 325is. It doesn't help because some of the wires don't match the '88-'90, some of them aren't used on my c101.

this is what I have.

'87 E30 connector, engine side.

1 Blue
2 Blue/White
3 Not used
4 Brown
5 Brown/Green
6 Green/White
7 Green
8 Not used
9 Not used
10 Blue/Yellow
11 White/Green
12 Grey mated to a brown
13 Green/Purple
14 Not used
15 Not used
16 White/Black
17 Not used
18 Black/Yellow
19 Not used
20 Not used

[Mike B.]

If you need a copy of the ETM to track down the functions of these wires, let me know and I will send you a copy for the '87.

[Bimmer335is]

that would help me out greatly.

[Mike B.]

PM me your email address.

[Bimmer335is]

pm'd

[triggrhaapi]

I read through the entire 50 or so page swap thread and found nothing helpful for me with s50 wiring in an '87 325is. It doesn't help because some of the wires don't match the '88-'90, some of them aren't used on my c101.

this is what I have.

'87 E30 connector, engine side.

1 Blue
2 Blue/White
3 Not used
4 Brown
5 Brown/Green
6 Green/White
7 Green
8 Not used
9 Not used
10 Blue/Yellow
11 White/Green
12 Grey mated to a brown
13 Green/Purple
14 Not used
15 Not used
16 White/Black
17 Not used
18 Black/Yellow
19 Not used
20 Not used

I think our cars use a modified early E30 M3 connector, the missing connections are in the glovebox on the C103 connector. I'm hoping this is the solution to my problem. This is the only known harness missing 8,9,14,15 and all functions seem to be moved to the C103 connection.

Hope this helps you!!

[PiercedE30]

Heres mine:
1990 325is to 1992 525i
C101 - Function - X20
1 - Alternator - 25
2 - Oil Level (static) - 1
3 - Not Used
4 - Coolant Temp (gauge) - 12
5 - Oil Pressure Switch - 23
6 - 12v feed for diagnostic plug - 22
7 - Ignition (switched) - 21
8 - Fuel Economy - 24
9 - Engine Speed (tach) - 20
10 - Oil Level (dynamic) - 2
11 - SI Reset - 7
12 - CEL - 8
13 - Fuel Pump Relay - 13
14 - Speed Signal - 14
15 - Starter (unloader relay) - 15
16 - Diagnostic Plug - 19
17 - Not Used
18 - Voltage during start - 18
19 - Not Used
20 - ABS - 3

[triggrhaapi]

Here's my wiring contribution for an s50 -> e30 m3 swap - might also help the m50 and 325i people.

http://www.cityofdust.com/s50/e30%20s50%20wiring.pdf

http://www.cityofdust.com/s50/e30%20s50%20wiring.xls

Confirmed, just now!! This is the correct wiring layout for the 87 325is. The C103 connector looks kinda like a 12v power connection from the inside of a computer case.

EDIT: Thanks Rev Engineer, you saved me a huge migraine headache, which I would have had if I had to try to read the electrical wiring diagram PDF for another minute.

[Jason89i]

typo.....pin 13 to 13 for older cars.

[kylebes1]

So did you get your car running?

I have seen people forget the ground strap. If you did that you will get nothing when you turn the key.

[matt]

So did you get your car running?

I have seen people forget the ground strap. If you did that you will get nothing when you turn the key.

Usually when the large ground strap is missing, the starter solenoid will click but the starter won't turn.

[triggrhaapi]

So did you get your car running?

I have seen people forget the ground strap. If you did that you will get nothing when you turn the key.

Which ground straps? You mean on the motor itself or on the harness? The motor has the grounds on the coils already, the harness isn't back from the electrician who's doing the work. Clearly if the chassis ground on the harness isn't grounded there's no juice to work with, ditto the coils.

[asubimmer]

I found the m42 plug info and I'm tryin to look at the m20 stuff and apply it to the m42 swap. this is what I have got for the m42 right now (if you see something that is wrong please let me know):


I'm not sure what to do with pin #6 and 7 on the m42 side. They are "#6 terminal 15 w/ fuse, #7 terminal 15 w/out fuse". Does anyone know what they should go to on the e36 side? Or even what they are lol.

[asubimmer]

after looking a little more I came up w/ this...better or worse?



also does anyone have the pin readout for the m50 plug so I know what pin is #1 etc. I need to know what pins are what on that plug.