Electrical Dilemma, Euroshark or other Guru...Help Please...

[De //m3]

So here's the deal...

Planning on doing the wiring this weekend:
Engine: Euro '82 735 M30B34(Grey market import as an '83)
E30: '86 325e w/Multifunction clock (No OBC)

So I grabbed what I thought were the two correct wiring diagrams from WEDOPHONES and spent yesterday "at work" pouring over the diagrams to match up all the C101 connections because the '82 735i Electrical manual from WEDOPHONES(The fron page ACTUALLY says 733) showed the C101 connector in hte manual and throughout the diagrams.

However, when I got home last night and popped the hood to verify the connections, there was no C101 plug on the engine harness, only the Small Square (C103?) plug. (Large female pins on outside with smaller female pins in the middle)

Am I an idiot and missed the C101 connector somewhere, or did someone disconnect it when we removed the engine from the 735i?

If I really do have the square connector and I used the wrong diagram, does nayone have the correct one, or at least a starting point before I get out the multimeter and do it all by hand?

Any help much appreciated. Thanks in advance! -Dylan

[euroshark]

Dylan, the engine harness that came with the M30 should have a rectangular C101 plug with somewhere between 8 and 15 pins. My guess is that you might have just missed it unless somehow it got chopped off! On the E23 I recall the fusebox being just about right on top of the drivers side inner fender, so if everything is in the relatively correct position, I'd think that the C101 should be easy enough to find. If you take a few pictures I'm sure we can identify it.

I still have all of my wiring notes from my 335i which used essentially the same wiring setup as you are working with, so when I get home I'll post what I have along with a few pictures.

[De //m3]

That would be great. I did see the square plug, Ijsut figured that C101 always meant the same, round plug. In that case I have located it but your wiring notes would be very helpful to me.

I think I identified 13 pins on the E30, and 11 on the e23

The ones I don't have are 2 of the diagnostic pins on the E30, the Oil Temp warning light on the E30, and the Coolant temp warning light from the E23.

I think that the last one is integrated into the tmep sensor on the E30 so there is no seperate wire required. I'll look at your notes and pics and see if I can get it all straightened out. Thanks! -Dylan

[euroshark]

Alright man, I found what I was looking for. My E30 was a 1984 325e and I also have pin number and wire color for the early Motronic harness that your engine should have.

C101 Plug for the E30 Harness to 1985
Pin - Wire Color - Function

01 - Solid Blue - Alternator Charge Indicator
02 - Blue / Violet - Oil Level Static
04 - Brown / White - Coolant Temp. Sensor
06 - Green / Yellow - Power supply with ignition on - Fused
07 - Green / Violet - Fuel Pump
08 - Black / Yellow - Power while starting - Starter solenoid
10 - Solid Green - Power supply with ignition on - NOT Fused
15 - Blue / White - Oil Level Dynamic
16 - Brown / Green - Oil Pressure Sensor
17 - White / Blue - Service Indicator Reset

C101 Plug for M30s with early Motronic to about 1985
Pin - Wire Color - Function

01 - Solid Blue - Alternator Charge Indicator
04 - Brown / White - Temp. Gauge Sensor
06 - Green Yellow - Diagnostic Connector
07 - Green / Violet - Power to Fuel pump
08 - Black / Yellow - Power while starting - Starter solenoid
10 - Black / White - Diagnostic connector / Airbag
12 - Solid Green - Power supply with ignition on - NOT Fused
14 - Brown / Green - Oil pressure switch
15 - Black / Blue - Service Indicator

As you see here there may be a few functions on one side or the other that aren't going to be used, but this should get you started! It might be necessary to jump the main relay if your C103/C104 plug in the glovebox doesn't match up exactly, but you can worry about that if it's the case.

This is a shot of the C101 plug. I don't recall if it's the one from the E24 or E30 harness, but they look the same... Just a few different wire locations.



Good luck tomorrow! PM me or email me directly if you need any more help.

[De //m3]

I think I got it all straight now although my wires were somewhat different than yours...

My E30 was an 86 so it has the later round C101, but everything worked out fine because I had a couple extra late C101s laying around to make up the other side.

All of the wires matched color for color, and I only ended up with one spare on each side. The M30 side was the oil pressure sender, which I will use to hook up a VDO gauge, and on the E30 side, the SRS (Wt/Bk) for the seatbelt indicator I believe.

So tomorrow the battery will be charged up and I'll try to get the engine to fire.

Is the C103/104 the three prong plug (Bl/Wt/Gr) in the glove box? If so, then this plugged right in also.

There was also a green box (Ignition Module?) in the E30 that has no plug on the M30 harness. I take it that this isn't necessary.

Also need to get ground, coil, and starter/solenoid plugged in, then the wiring shoudl be good except for one spare wire in the glovebox.

Otherwise I just need to get fuel lines hooked up and some oil in the engine to turn it over. The one snag (Bonus for later) is that this engien had an oil cooler that i dont have so Ill have to temporarily close those holes until I get one.

More updates tomorrow!

[euroshark]

Sweet! Sounds like you've got pretty much everything covered, let us know how it goes!

[De //m3]

Well didn't get quite as much done as I had hoped, but good progress non the less. I have not tried to turn the engine over yeat, but all of the electronics are working with no problems. My only warning lights on are Engine Oil(The pan is empty), Coolant Level(There is no coolant reservoir hooked up yet), Low Beam(There is a faulty wire), adn one more I can't remember.

I have a couple questions before I try to start it though.

I have a few wiring issues:

1)There is one red wire, it comes off of the engine harness right where all the C101 wire come out, and I believe it goes to the (+) Positive side of the starter, because I have no wires connected to the starter yet. Is this correct and also do I need a (-) Ground connected to the starter?

2) There is a single wire (Bk/Wt) in the glovebox that had a conneciton with the old harness and has no connection now. Its just a single small wire with a single connector.

3)Finally, there was no resistor connected in the spot near where the engine harness passes through the firewall, I pulled a bunch form the junkyard and only one has 5 prongs like the socket. I couldn't find the diagram in the electrical guide so I'm not sure exactly what the resistor layout is supposed to be, but the current one matches all 5 slots, are they all the same or do I need to get an exact match for the resistor.

After that, I just need to temporarily cap of the oil cooler outlets at the filter housing, or loop them, and hand crank the engine to make sure its free, then I'll fire it up.