No start turns to crank no start

[getty150]

Just as I get off the off ramp the M54 dies slowly. Air shuts down, radio shuts down and then transmission symbol appears. Once at the stop light she dies with only a single click when the ignition is turned.
After the tow to my drive way and replacing of the following...

Freshly charged battery
Fuel pump
Alternator
Crank sensor
Starter
Ignition switch
Hot water valve (having fun now)
Replaced the cowl (having more fun)

Finally got my scanner from my neighbor...
Cleared the existing codes and when the dust settles...Iam left with code 27A4.

All experienced input welcomed.

[Effduration]

Originally Posted by getty150

After the tow to my drive way and replacing of the following...

Freshly charged battery
Fuel pump
Alternator
Crank sensor
Starter
Ignition switch
Hot water valve (having fun now)

..I am left with code 27A4.

Let me look that up for ya.....Oh, It appears to be a code related to how the EWS (immobilizer) and DME are synched to each other.

Your symptoms sound like a failed alternator leading to insufficient battery voltage. If that is true, your battery light should have been on.

Did you test or measure volts from Battery or alternator before replacing them? or did you just light the fuse for the parts cannon.

I would search on how to re-synch EWS with DME, probably with INPA or some BMW-specific 2-way scanner, and see how that works.

[X5chemist]

A copy and paste from a post I found while troubleshooting a parasitic amp draw on F11.

EWS has 2 protections, in all the cars:
-EWS to key mismatch = no crank
-EWS to DME mismatch = no spark/no fuel injector pulse, but it will crank.
A INPA EWS-DME sync should fix it.

[andrewwynn]

Originally Posted by X5chemist

EWS has 2 protections, in all the cars:
-EWS to key mismatch = no crank
-EWS to DME mismatch = no spark/no fuel injector pulse, but it will crank.
A INPA EWS-DME sync should fix it.

That's some very helpful feedback. Why on earth BMW decided it should crank when it won't allow a start is beyond stupid but seeing that is a known thing is very helpful.

[Clavurion]

Originally Posted by andrewwynn

That's some very helpful feedback. Why on earth BMW decided it should crank when it won't allow a start is beyond stupid but seeing that is a known thing is very helpful.

That's quite simple. Engine control unit (DME/DDE) has nothing to do with starter activation. If the immobiliser wouldn't have that second functionality of preventing fuel injection the engine could be started by just hot wiring the starter when ignition is on.

[andrewwynn]

That makes perfect sense but why let the starter activate from the key when the injector/spark is disabled also. And why no obvious dash icon for EWS? (Or are 100% of the posters online missing a giant with a red )

Every car besides BMW that I've worked on has a key no workie dash icon for immobilizer issue. There's no sound logic for a legit owner with an EWS problem not to be obviously alerted to the actual problem.

[getty150]

Originally Posted by Effduration

Let me look that up for ya.....Oh, It appears to be a code related to how the EWS (immobilizer) and DME are synched to each other.



Your symptoms sound like a failed alternator leading to insufficient battery voltage. If that is true, your battery light should have been on.



Did you test or measure volts from Battery or alternator before replacing them? or did you just light the fuse for the parts cannon.



I would search on how to re-synch EWS with DME, probably with INPA or some BMW-specific 2-way scanner, and see how that works.

Absolutely right!
and the suggestions match my research results. Greatly appreciate the responses I'll go into action on the next days off next week...keep you updated...got to get a scanner that will link the two.

[andrewwynn]

I used to use foxwell NT510 then upgraded to the NT710 worth every penny.


Sent from my iPhone using Tapatalk Pro

[getty150]

Originally Posted by andrewwynn

That makes perfect sense but why let the starter activate from the key when the injector/spark is disabled also. And why no obvious dash icon for EWS? (Or are 100% of the posters online missing a giant with a red )

Every car besides BMW that I've worked on has a key no workie dash icon for immobilizer issue. There's no sound logic for a legit owner with an EWS problem not to be obviously alerted to the actual problem.

What do you think? common for the 06 model...
https://r.tapatalk.com/shareLink/top...ink_source=app

[getty150]

I think this is where I'm at with the M54 X3...

The mentioned code indicates that*the synchronization between the EWS and engine control computer is not correct. This will result that the car is cranking over as as the EWS itself is seeing a valid key but prevent the car from starting as the ignition and fuel system are disabled.Jun 4, 2023