[greye93]

Hello all,

From the begining -

The battery died. Jumped & worked fine for a few days.

Decided to replace the battery, when I did it went into limp mode and wouldn't allow me to go over 20 mph. (Im assuming because I did not code it.)

Put the old battery on, after on a charger and being at full voltage.

The car than ran for the next week fine, until when randomly driving it shut off and will not start, but cranks.

I replaced the alternator, and tried with the new and old battery both fully charged.

Not sure why it wont start.

Pulling two consistent codes of:

A0B4 - CAS: Engine Start, starter operation.
2D2A - DME: Diff-pressure sensor, intake manifold adaptation


Any help would be very appreciative!!!

[gbalthrop]

Originally Posted by greye93

... ran for the next week fine, until when randomly driving it shut off and will not start, but cranks... Not sure why it wont start.
A0B4 - CAS: Engine Start, starter operation.
2D2A - DME: Diff-pressure sensor, intake manifold adaptation

2D2A is ONLY DME Fault Code?
Starter ALWAYS Cranks Engine, but Engine does NOT fire?
You have A0B4 CAS Fault Code, & NO other DME code other than 2D2A?
Will your Scan Tool/ Diagnostic Software display Engine RPM during Starter Cranking?

That RPM signal is based on Crankshaft Sensor Signal, and should be in 180 - 200 RPM range during Cranking.
If DME receives NO RPM signal from Crank Sensor, it CANNOT time Spark & Injector Pulse: Crank, NO Start.
A0B4 CAS Code means CAS has sent KL50 Voltage to Starter Solenoid, but DME gets NO RPM signal from Crank Sensor.

Don't just assume your Crankshaft Position Sensor needs replacement. Provide the Last-7 Characters of your VIN and we can
suggest how to TEST the wiring between Sensor & DME. If you can visualize the Crank Sensor Connector (under the Starter, at
rear of the Intake Manifold) with bright light, see if Connector/ wiring is Loose/ damaged.

ANYONE accessed Crankshaft Sensor from Underneath to either Replace it, or to Test Connector? Any "Tricks"
to share to do either WITHOUT pulling Intake Manifold?
George

[greye93]

Yes it cranks, but does not start.

I have also have seen the following codes come on, once then not again once reset.

9c6c
c588
2dec
2acc
2a9a
2d2a

These all came on once, but once cleared have not seeen again.

Thankyou

[Bims328i]

It's fairly easy to approach it from above. Removing the second intake elbow section after the airbox will give you space to access the connector for testing.

5th post down there is some more information on accessing it from above.

https://www.e90post.com/forums/showthread.php?t=2077792

[greye93]

My vin is WBAPH7C56BE678536.

Is it possible that the DME is fried?

[greye93]

I went to the car today. It is pulling about 170 rpms when trying to start.

i am also now getting the code 2a9a...

Any idea on what that could be?

[gbalthrop]

Originally Posted by greye93

I went to the car today. It is pulling about 170 rpms when trying to start. i am also now getting the code 2a9a...

2A9A Definition & Fault Info Link (see Service Notes for suggested Tests:
2A9A | DME: Crankshaft - inlet camshaft, synchronization | MSV80 | Engine electronics
https://bmwfault.codes/XMLDiagView?d...EAMQA4ADAANAA=

Need to develop a "PLAN" for diagnosis/ Testing. Please answer following questions:
1) What Make/Model Scan Tool do you have?
2) Do you have a Multimeter? What battery voltage measured at Jumpstart Terminals?
3) How far away is the vehicle? Is there an electrical outlet available?
4) Have what is needed to charge battery where vehicle located? 170 RPM during Starter Cranking suggests marginal
Battery Voltage. Needs to be at LEAST 12.0V. Charge or connect Jumper Cables at Jumpstart Terminals (NOT at battery).
5) Read/Report ALL Fault Codes in DME.
6) If your Scan Tool will display "Freeze Frame Data", please provide FF Data for each DME Code.
https://www.obdautodoctor.com/tutori...ame-explained/
7) After recording ALL DME Codes & FF Data, CLEAR all DME Codes, then Crank Starter for ~ 5 seconds.
8) Read and Record ALL DME Codes & FF Data AGAIN, and post here. Post info recorded in (5,6) & (8), SEPARATELY.

Your OLD codes indicate PAST/ Current(?) issues with Crankshaft/Intake Cam Synchronization (2A9A), DME Relay (2ACC) &
Battery Exhausted (2DEC), battery voltage LESS than 9.5V. Latter would prevent Starter Cranking, probably OLD.

Proper Diagnosis of "Crank, NO Start" issue requires time & effort. That's why many folks just "Throw Parts". If you will
answer each of the questions above, we can suggest "Next Steps" YOU can take with available equipment.
George

[greye93]

This is a great write up.

I do have a multi meter and code reader with freeze frame.

I should be out to the vehicle soon and can check.

Thank you very much. Looking forward to hearing from you soon!