1.1 TO 1.3 Motronic on a 1986 325i

[Speedtouch]

I would think it's OK to leave the ECU in the engine bay for testing, after all, the E34 has it in the engine bay, next to the bulkhead!

It may need to be earthed though, and don't forget the engine earth strap.

Theoretically, all you need is the ECU connected to coil and injectors, hook up a battery and starter motor and away you go.

[gooner1]

Thanks Maurice.

[gooner1]

http://www.e30zone.net/e30zonewiki/index.php/C101

[gooner1]

Before I enlarge the hole in my Bulkhead, how do I remove the plastic
casing from the Ecu lead plug
Have undone the three small screws but it doesn't seem to want to come apart.

[Brianmoooore]

Prise the rubber gasket out, and ease the plug out by pushing the wiring into the plug.

[gooner1]

Thanks, again, Brian.

[gooner1]

Pulled back the cover from the C101 plug to look for the dreaded
Brown wire in Pin 20, none there.
But there is a Brown wire in what appears to be Pin 11
Why the , according to the Wiki the Brown wire should be in Pin 4, which would be the Temp
gauge.

Stuck a matchstick in the relevant Pin No to check, and it's definitely in Pin 11.






Unless of course I'm reading the Plug wrong.


Doesn't appear to be a Brown wire in the Engine side of the C101 plug either, which I presume is good news, or is it

[Speedtouch]

Pulled back the cover from the C101 plug to look for the dreaded
Brown wire in Pin 20, none there.
But there is a Brown wire in what appears to be Pin 11
Why the , according to the Wiki the Brown wire should be in Pin 4, which would be the Temp
gauge.

Stuck a matchstick in the relevant Pin No to check, and it's definitely in Pin 11.



Unless of course I'm reading the Plug wrong.

Unless I'm much mistaken, that's a socket, not a plug! In which case, if you reverse the pinout diagram, that would correspond to pin 4.

[gooner1]

Jesus wept, I'm now officially Thick, but relieved .
Thanks Maurice.

[Speedtouch]

No problem - an easy mistake to make!

[Brianmoooore]

?????????? There shouldn't be ANY brown wires in the C101, except for the possible one on pin 20. Only brown wire from the engine loom to the car should be the one that goes to the LH suspension turret, and this one may be brown/orange rather than brown.

[gooner1]

Brian, here's a pic of the female half of the C101 that comes directly from
the Bulkhead side of the car.



Very definitely Brown.


As Balotelli would say, " why always me?"

[Brianmoooore]

If that's pin 5, it should be brown/black. Earth it with the ignition on, and the oil pressure light should light up.

[gooner1]

It's Pin 4 Brian.

The one with the matchstick in it is this pic.

[Brianmoooore]

Pin 4 should be brown/purple, and if shorted to earth, should make the temperature gauge go to full hot.

[gooner1]

Pin 4 should be brown/purple, and if shorted to earth, should make the temperature gauge go to full hot.

So, stick battery back on, length of wire from Pin 4 to Engine block
with ignition on, and that should make the temperature gauge go to full hot, yes?
No need to connect Ecu or anything else yet?

[Speedtouch]

According to the wiring diagram, that is the case. A26 (Brown/Violet - "BRN/VIO") goes straight between the temp gauge and the Temp sender.

So, as long as you're getting power to the clocks, shorting that Brown/Violet to ground will make the temp gauge read full hot.

http://www.autolib.diakom.ru/CAR/BMW/19 ... /fig08.pdf

[gooner1]

Bingo!!!!!!
Followed advice given and Temp Gauge shot to the Red.

All in all, a satisfying couple of hours, managed to seperate the Ecu lead
from it;s plug/socket. Feed it through the Bulkhead and connected the
alternator, coil and one lead to the starter motor.

Then I realised I was supposed to leave the Ecu plug/socket in the engine bay
to make it easier to pull my current lump out. Doh!!!!!!!!


Thanks for all the help btw.

[gooner1]

Nearly there, just a few questions more.
Re the starter motor, I have one red wire which I think goes
to the larger of the two studs, and 1 thinner Black/yellow ,,also one thin black/Green
which I presume go to the smaller of the two studs. Correct

From the + Battery terminal, I have this thick Black lead with a large connector, pic below



If it helps this lead also has a kind of ribbed covering over part of it;s length.

Lastly, there are these two thinner black leads that come from near the Coli wires and the Oxygen Sensor, pic below.


The last two wires are, I think, Ground wires, but where do the have to be placed

TIA.

And yes, I do know my coolant overflow pipe needs sorting.

[Brianmoooore]

Big black wire from the battery and the red wire (from the alternator?) both go to the outer terminal on the starter solenoid with a 13mm nut.
Black/yellow to the stud with the 10mm nut, and black/green to the stud with the 8mm nut.
The two wires in the second pic. aren't black - that's just an outer sheath. Turn back the rubber sleeves on the end or back into the wiring box to see their real colours.
If they are earths they will be brown or brown/orange, and go to the earthing terminal on top of the RH suspension turret.

[gooner1]

Will it be ok to fit the two Brown Wires to the stud underneath
the Strut bar bracket, to use as a Grounding point, and do they have to go to the same stud?

[Speedtouch]

As long as they get a good earth, they can go anywhere you like! And not necessarily to the same stud.

[Brianmoooore]

The two wires in the second pic. aren't black - that's just an outer sheath. Turn back the rubber sleeves on the end or back into the wiring box to see their real colours.

[gooner1]

The two wires in the second pic. aren't black - that's just an outer sheath. Turn back the rubber sleeves on the end or back into the wiring box to see their real colours.

Done as you previously suggested, turned back the outer
sheath, and both wires are Brown, Brian.


Connections on starter motor were different though.
13 mm nuts on the inner and outer studs, and a Male spade connector above them.

[Brianmoooore]

If they are both brown, then they both go to earth. That hole in the bracket between the turret and the coolant bottle looks tempting if they'll reach.
For your starter motor, big red and big black from the battery to the outer 13mm nut, black/yellow to the spade terminal, and black/green to the inner 13mm nut.

[gooner1]

Should the Engine crank or starter engage , without the CPS being installed?

[Brianmoooore]

Yes.

[gooner1]

Then I have a problem.
All dashboard lights, indicators, Headlights working fine.
But car not cranking, not even a click from the starter motor, cant hear the fuel pump priming, or ICV buzzing.

Battery has been put on charge over night , so will try again later this evening.
Suppose the Coil should be the first thing to check, right

[Brianmoooore]

Starter motor is a very simple circuit which is independent of any other engine related circuitry. It should still work if you stripped every single component from the engine, just leaving the bare block, motor and wiring.
First test is to see if the starter engages when you link together pins 11 and 14 of the diagnostic socket.

[gooner1]

Stuck a known working Battery on, bridged what I
think are pins 14, 11, in the diagnostic socket.

Getting a clicking from a relay in the fuse box, battery light on the Dash and service lights flashing. Is this pointing to a bad connection on the starter?

[Grrrmachine]

http://www.e30zone.net/e30zonewiki/inde ... Plug_Start

[Brianmoooore]

Is this pointing to a bad connection on the starter?

Points to you haven't fitted the engine to body earth strap.

[gooner1]

Brian, body earth strap has never been disconnected.
That's not to say it hasn't become dislodged though, so will
check that tomorrow.

[gooner1]

Starter now working. Turns out there are 2 spade connectors on mine.
One at the top of the Solenoid , which is plain view, and one right at the bottom
which I couldn't physically see but found after checking the Body earth strap
then having a grope of the starter itself.

Now to find out why it will not fire up.

[gooner1]

To ask a variation of an earlier question, would the Engine start , without the CPS being installed?