Tools needed: fairly sensitive digitial voltmeter -peak hold function would be useful if singlehanded
Symptoms:EML light came on, and Bank 1-6 shut down.

Identify failed bank by disconnecting DK one by one, if disconnection makes no difference then that is the failed bank.

Initial checks:
No Fail codes.
1-6 throttle won't move on command, 7-12 works fine.
Swapping DME's over had no effect
Swapping throttles over had no effect

Initial Conclusion:
Not DME problem
Not DK problem
Could be wiring/plugs
Could be INPUT SIGNALS (must be unique to the failed bank) - crank position sensor - cylinder identification pickup -
Could be fuel pump - fuel pump fuse - fuel pump relay
Could be EML unit

Additional checks:
EML light comes on before engine start
SO cannot be cylinder identification pickup
OR crank position sensor

Fuel pump - relay- fuse check ok

Measure DK voltages
When turning the key to position 2 - before engine start - measured with DK disconnected
7-12 (the good side) receives 12v to pin3 and 6 v to pin 5. then both pins go to zero
6-12 (the bad side) receives 7.2v to pin3 and 4.2v to pin5. These values remain.
The only differences between the throttles are on pins 3 and 5. All the other pins give matching readings.
SO wiring looks good on 6-12 bank -- Power is being delivered -- maybe plug
OR problem is with DK output circuit of EML

Final conclusion:
Blown Transistor on the EML ! ! !
" I opened up the EML to see if there were any obvious reasons why it wasn't delivering a 12v initialisation pulse to throttle pin 3, and one of the power transistors had scorch marks all over the heat shield, and was SPLIT IN TWO..."
This is NOT common problem

WARNING: DK output circuit does not have short circuit protection so a momentary short in the driving circuit may blow the output transistor(s)
BE VERY CAREFUL WHEN CHECKING VOLTAGES/RESISTANCES AT THE DK PLUG

Repair:
Bought replacement EML unit

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I got the car as a theft recovery, with a blown transmission and no EML light.
The car drove ( leaked all fluid in a matter of 100feet) but it was in Fail Safe mode.
I changed cluster tranny, eml, abs, dml modules and nothing changed. A new AST switch fixed the blinking ast light.
So I still had no EML light and no tranny gear display.
Clean all connectors, new crank triggers. A new a-m switch, mine was broken inside, and cleaning the shifter select mechanism
solved the tranny gear display issue in the cluster. then VOILE, car had gear shifter display in cluster then car went to limp mode.
Least it was drivable in fail safe mode. Engine runs and starts very well! in fail safe mode car is smooth. slow but smooth, all new plugs burning well.

a week off work playing with car, swapping every major component and blindly screwing around got me no where.


Found BMW repair manual with diagnostics and theory or operation. and I was in business.

EML light always gets power from fuse block. ALWAYS key on or key off.
The EML computer always sends the EML led lights 12volts giving a potenial difference of 0volts therefor no light coming on.
Upon start up the EML ecu switches that wire from +12volts to ground and then the EML light comes on.
The ECU then measures resistance and says "cool the lights work" then gives the LEDs +12v again shutting the lights off.
In a fault it has to know that it can be able to signal the driver there is a problem... Okay thats easy enough. Easy.

Check the under dash connector, +12v.
Check at connector at cluster, +12v.
Check at both sides of both LEDs +12v.
Check at connector at cluster, +12v,
Check at connector in engine bay ( big round one beside diagnostics) +12v at both pins.
Check continuity between plug and EML connector. Nothing.

The antifreeze housing has that nice little catch lip and little hole dumping antifreeze on the firewall.
Yep right on top of the main engine harness.
After years of being in 100f heat in Texas the harness was compromised and allowed water / antifreeze in.

All the splices that were in that harness were corroded, but the EML splice was the only one that had had failed completely.
I had to cut back 8 inches to get to "clean" wire and soldered and heat shrunk the eml and all the other splices there.
Bought some self sealing wiring harness wrap sealed it all back up and voile car is running 100%.

Photo of cut wires ready to be re-spliced shown below.

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