ALMOST done.. but what about these?

[r4esh]

I think this is my 5th post saying "just finishing up".. but as you can see I'm almost there.

For starts.. yes I'm thoroughly looking through the 700 page manual trying to make sense of a lot of the diagrams + even find what I'm looking for…

I'm a little confused on the positive and ground connections. On the e36 harness, passenger side, there are 2 main positive plugs and 1 negative cable right? I took a picture to maybe help identify them. Can someone confirm this is correct? EDIT: The positive lead coming from the passenger side splits off one into the starter and the other would go to the e36 fuse box, but in this case isn't used.

^ OR if its easier, maybe could some just explain the layout of the positive and grounds?

On the same note of that, I've got two unconnected "grounds?" on the driver's side down by the alternator/oil pan. EDIT: Still haven't verified these...


Oh and then there are these I still don't know about… (EDIT SEE BELOW FOR ANSWER)

EDIT: Confirmed this is for the O2 sensor (clipped wire) and the reverse light.

I think that wraps it up and then I'm ready to start the car! Thanks again for your help guys!

[herlsy]

First off, what year harness are you using? is this m52 to OBD1?


Pic 1 looks right, the cable should connect there and then splits into alternator and starter.

Pic 2 looks like it would probably go to the starter, what color are the wires? (they should be uncovered at some point, possibly near the rubber covering)

Pic 3 where does that cable route to? Is your MAF plugged up?

[r4esh]

First off, what year harness are you using? is this m52 to OBD1?


Pic 1 looks right, the cable should connect there and then splits into alternator and starter.

Pic 2 looks like it would probably go to the starter, what color are the wires? (they should be uncovered at some point, possibly near the rubber covering)

Pic 3 where does that cable route to? Is your MAF plugged up?

It's a m52 engine with obd1 95 m3 harness in a 1989 325is e30.

K. Pic 1 sounds right. On pick 2, I'll double check the colors, but why the starter?? I don't think they would even reach the starter. Maybe alternator ground? I'll get back to you on the colors. On pic 3 the MAF IS plugged in, so its not that. I don't know exactly where that cable routes to as it is VERY long... it could just about go anywhere.
I bought the harness from the forums... is it possible someone gave me the harness from an automatic car and not a manual? and that those extra cables are for the automatic car??? I can't I.D. these so that's my guess. (arggh!) Either that or maybe they are for the o2 sensor and something? Currently I don't the o2 sensor hooked up anywhere... I still haven't picked up an OBD1 sensor and I havn't heard you can use the OBD2 ones; does it matter? I don't see anywhere else where the o2 sensor would connect to the harness.

[rpm620]

pic3.. the connecter might be your charcoal canister valve connecter. i think its hard to tell where the wiring is coming from in the photo

[r4esh]

pic3.. the connecter might be your charcoal canister valve connecter. i think its hard to tell where the wiring is coming from in the photo

I've got the charcoal canister hooked up already.

[Artful Dodger]

I think the last picture might be the cables that go to the o2 sensor and the reverse light switch on the e36 trans.

The connector that is still there would be for the o2. the one that is missing a connector would be for the reverse switch. the connector is a small 4pin connector that has a twist lock similar to the x20 or c101.

[Wh33lhop]

It's a m52 engine with obd1 95 m3 harness in a 1989 325is e30.

K. Pic 1 sounds right. On pick 2, I'll double check the colors, but why the starter?? I don't think they would even reach the starter. Maybe alternator ground? I'll get back to you on the colors. On pic 3 the MAF IS plugged in, so its not that. I don't know exactly where that cable routes to as it is VERY long... it could just about go anywhere.
I bought the harness from the forums... is it possible someone gave me the harness from an automatic car and not a manual? and that those extra cables are for the automatic car??? I can't I.D. these so that's my guess. (arggh!) Either that or maybe they are for the o2 sensor and something? Currently I don't the o2 sensor hooked up anywhere... I still haven't picked up an OBD1 sensor and I havn't heard you can use the OBD2 ones; does it matter? I don't see anywhere else where the o2 sensor would connect to the harness.

The O2 sensor plug for my NV M50 was a big 4-wire round plug with a twist-type fastener (think C101) and it was held facing rearwards, just below the starter. You can see it here. My guess is for all the OBDI motors it was the same.



If you don't have that plug then that's probably what it was before they clipped it. I'm not sure what the other plug was, have you hooked up the IAT sensor on the bottom of the IM, towards the firewall?

Those other two wires look like they go to the alternator. The alternator grounds out through the block, but my E34 alternator had a rubber cover you had to pull back, and two wires almost just like that. One should be thicker gauge and one should be smaller, you'll know where to put them. (yes, that's what she said)

[herlsy]

The above pic looks like an e34 setup though, e36 o2 was longer on the harness side.

I thought that pic 3 might have been the o2/reverse also, but it throws you off when it is at the front of the car.

[Gnarles]

Easiest way to figure out what plug you have is to get the pinouts for the DME connector and check continuity between it and the sensor plug in question. Figure out which pin on the DME has continuity with your plug then lookup than pin number to figure out what sensor it is. Wiring colors can differ, so this method will give you the most accurate results.

[r4esh]

Thank you everyone again for being so helpful/informative.

I'm guessing the cables in question on 'Pic 3' are the o2 sensor and the reverse light like someone suggested... I didn't know there was an extra cable for the reverse light. But seeing as how I don't have an o2 sensor hooked up / havn't found the connector to do so, I think its safe to say that's what it is. Here is a picture of the wires reveled and colors exposed.


Sorry to have so many questions, but to keep things simple:
Q1: Is Pic1 in the original post right?
Q2: Can someone confirm where those go in Pic2 in the original post? Also, there is already a lead coming from the starter to the alternator, and a blue cable (i think ground) going to the harness from the alternator as well.
Q3: I think we've confirmed that the wires in Pic3 ARE for the o2 sensor and reverse light - so - Can i use the obd2 o2 sensor? What will happen if I run the car without an O2 sensor hooked up? And where does the reverse light plug into?

Q4: This one I'm worried about: When splicing my c101 connector to the harness I stumbled across 2 green cables coming from Pin 7 on the c101 (ignition pin), one was thick and one was small. On the x20 (e36) side, in the ignition pin it had the SAME thing... soo I said, both e30 and e36 have this, so I'm going to connect both, BUT someone else here said NOT to connect these..? Anyone else come across the same thing?

Sorry for long elaborate posts -- just want to try and eliminate as many questions as possible + get clear answers. Thanks again!

[r4esh]

The O2 sensor plug for my NV M50 was a big 4-wire round plug with a twist-type fastener (think C101) and it was held facing rearwards, just below the starter. You can see it here. My guess is for all the OBDI motors it was the same.

If you don't have that plug then that's probably what it was before they clipped it. I'm not sure what the other plug was, have you hooked up the IAT sensor on the bottom of the IM, towards the firewall?

Those other two wires look like they go to the alternator. The alternator grounds out through the block, but my E34 alternator had a rubber cover you had to pull back, and two wires almost just like that. One should be thicker gauge and one should be smaller, you'll know where to put them. (yes, that's what she said)

Sorry, but whats the IAT sensor? And whats the IM?
There are 2 cables plugged into the alternator already, one thick red one, and one small blue one.

Easiest way to figure out what plug you have is to get the pinouts for the DME connector and check continuity between it and the sensor plug in question. Figure out which pin on the DME has continuity with your plug then lookup than pin number to figure out what sensor it is. Wiring colors can differ, so this method will give you the most accurate results.

I'll try and do this later... my multimeter is crapping out on me though.

[herlsy]

Sorry, but whats the IAT sensor? And whats the IM?
There are 2 cables plugged into the alternator already, one thick red one, and one small blue one.


I'll try and do this later... my multimeter is crapping out on me though.

IAT - Intake Air Temperature
IM - Intake Manifold

How many wires do you currently have going to the starter?

[r4esh]

IAT - Intake Air Temperature
IM - Intake Manifold

How many wires do you currently have going to the starter?

There is 1 from the positive battery terminal that splits off into two positive lines, one that is plugged into the started and the other I'm not sure where it goes, then from the starter, there is the cable that runs off to the alternator.

I'm 95% sure the IM and IAT are plugged in + fine.

[r4esh]

Bump... I Just confirmed the wires from Pic 3 ARE INFACT the o2 sensor and reverse light.

And also some search yielded that the the positive wire coming from the battery that splits off into two lines, one starter, and the other goes to the e36 fuse box.. which in this case isn't used, so this wire is redundant. What's everyone doing with this wire? Clipping it back and taping it off?

[Wh33lhop]

There is 1 from the positive battery terminal that splits off into two positive lines, one that is plugged into the started and the other I'm not sure where it goes, then from the starter, there is the cable that runs off to the alternator.

I'm 95% sure the IM and IAT are plugged in + fine.

On the starter, there should two huge wires going to the same post on the solenoid, then there should be two other wires going to the posts of the solenoid--one to the K7 (IIRC) unloader relay and one to the start signal wire. I'm going off of memory for a 4-wire starter, so somebody correct me here. My early model had a 3-wire starter, for what it's worth.

According to Wedophones, the '95 S50 harness had two O2 sensors: http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf Strange. Anyway the wires for both O2 sensors are the same color: black, yellow, green/blue stripe, and one unlabeled, but it goes to ground distribution, so most likely brown or brown/red. Looks like the final one in the picture is brown/red, so I think that's confirmed.

The backup light switch definitely has a blue/yellow wire going to it (Page 6322.0 in the ETM, BL/GE = Blau/Gelb) so I'd say we know pretty well what the second plug goes to.

Edit: took too long to look through and post. Good job, now find an O2 sensor and plug to attach. It will run alright without one, but if you run rich for TOO long I've heard you can eat up your cat. I'd recommend getting one as soon as possible.