4 replies to this topic

[David Wayne]

My '97 MPi had it's heart removed, doctored, reinstalled, and now it doesn't start.

 

(Note: I live in Canada and the my Mini guy is an hour away.)

 

Engine and front sub removed for some front end work, new mounts and bushings, gearbox leaks, clutch plate, suspension (dampers, cones & Hilos), basically everything you should replace when you pull the front end apart.

 

Engine and subframe was put back in, sensors hooked up.  Charged battery reconnected, red immobilizer LED flashing, key fob activated to unlock, LED winked off, key inserted, turned, Immobilizer LED flashing, nothing else.  Suspected Imobilizer.

 

When the engine was removed one of the White Slate (grey) wires was cut, one end was turned back an fed back into the loom. It was reconnected.

 

Moving the MFU relays (MEMS relays) by hand: power to fuel pump, and engine turns over. Moving the wires of the MFU must have reconnected something, because now it turns over with the key, no fuel pump, no spark.

 

Thinking that maybe there was a reason why the WS wire was cut, it was re-cut.  No change to it not starting.

 

Pulling the MEMS out and looking at the connectors, we found this:

 

The red line indicates the WS wire temporarily connected, the yellow line is a White Black Wire (Ignition Coil), which was found broken when I inspected the wires/connectors to the MEMS. Still no change to it not starting (no fuel pump, no spark). (And there is a second WS wire - one is the Immobilizer Signal and the other is a second Ignition Coil input to the MEMS Control Unit.)

 

This is getting long, so:  with regards to MEMS Control Unit, does anyone have a guide to the values of the signals at the two connectors.  Also I've looked the MPi topics over and found that the Crank Position Sensor has been mentioned as a fix. Is it? I am (almost) lost and grasping at straws, because I really don't want to buy a MEMS Control Unit, or convert it to carbs.

 

Anything will be very much appreciated.

 

[mini 4o]

 Circuit%20Diagrams.pdf   1.06MB   62 downloads

[David Wayne]

Thanks Mini 4o. I will have to come up with a pin out table, i.e. Pin 7 goes to O2 sensor - meter should read ___ ohms/volts, Pin 32 goes to crankshaft postion sensor - meter should read ___ ohms, etc..  I have a sensor diagnostic sheet somewhere, it will come in handy.

 

With the wonderful electrics on the Mini, the big thing was to find out if any of the sensors, if not connected (because of a broken wire), would give the same fault indication.

[mini 4o]

David      if you need anymore of the workshop manual ..just drop me an email, I know very well what its like to be mourned.

 

john

[David Wayne]

Well, as it turns out my Mini guy isn't much of an Mini electrical guy.  He hooked the Main Ground from the MEMS Control Unit to the Starter, "Thought it was just another ground line." So that was fixed, and it is running quite nicely. Thanks once again for the wiring diagrams.

 

My next mystery: Figure out why the Ignition Coil wire off MEMS Control Unit, Pin C159-26 was cut and tied back. Well, other than the fact that It doesn't start with it connected.