325e to M50; no C101?

[MSFIT]

I'm down to wiring, I've got the body side off the e36 x20 w/ pig tail's, can't find the body side of the e30 (84 325e) =/

I found something about square vs round c101, do I have square? Will I need to wire straight from the fuse box to my c101?

[herlsy]

Yes you have a square plug, just wire it to the square plug.

[MSFIT]

So just to be clear:

Connector to use:



The 10 wires from that and the Tach wire from connector on instrument panel to the c101. Is that all that can be connected? Should have started with a later model car?

[Jean]

That's an early c101, no big deal. There are only a few wires needed to RUN the engine, rest are extras. On the early cars like yours no everything (check engine light, mpg, tach for example) go through the c101 so you'll just have to run some extra wires from the m50 side of the harness individually. It really is not a big deal or difficult.

You can either convert that rectangular c101 into 20pin or even better a 25pin c101 and not run an adapter for a cleaner look/install. Or make / pay for an adapter.

[MSFIT]

Awesome, just wired the body side c101 I had to the square connector off the old engine harness. This is like you said, Jean, kinda converting it to a c101 25 pin.

There were 7 wires from the square to the round 25 pin:
Alternator Charging
Coolant Temp Sender
O2 Relay
Fuel Pump
Starter
Ignition Switch
Oil Pressure Switch

What will I need to wire individually into the 25 pin c101?

What I see left on the other wiring diagrams are:
CEL
Speed Signal Input
Starter thin
Fuel Consumption
Engine speed

I guess my question is, where(what wires) are these on the car?

Edit for pic:

[Jean]

CEL / Speed Signal / Fuel Consumption and Engine speed inside the car / cluster. There a 3pin connector above the glovebox under the dash.