35d cranking but not starting
 

Hi guys,

Last week my 35d died while I was driving it and it refused to start again.
It was cranking without an issue, but wouldn’t fire. There were a series of errors on the screen including “fault in drive”, “driving stabilisation failure”, “DBC failure” and “fuel pump”.

I plugged in my basic OBDII scanner I had at home and no codes were displayed.

The roadside assist guy tested the battery and said it was fine, so I had it towed to the dealer.

The dealer has had it a week and yesterday when I went in, they said it was probably a comfort access control module issue and possibly a bad battery too. They’ve also said they’ve been able to start it and the issue is intermittent. They said the module would have to come from Germany pre-coded to my car.

Now, I’m fairly certain my car doesn’t have comfort access. I even put my VIN into a BMW VIN checker and it didn’t come up as an option on my car. Even if it did, would this cause a cranking but no start issue? I can’t find any evidence on any forums that this could be the cause of my no start issue.

Thank you in advance!

Just curious have you checked starter motor despite it not showing up in faults?

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LOL! I don't know if you have CAS or not but that statement gave me a good laugh!

I am afraid the diagnostic abilities of dealers are at an all time low. What did they do to get it to start or is that also a fairy tale?

Since you are getting some seemingly unrelated failures it could be a fuse went or a bus is down?

1. You were DRIVING and it died. DO NOT focus on 'why wont it start'. IMO it isnt a starter failure- starters dont die while driving and dont stop a running car.



2. Dealer is full of shite. They are lost. It is IMPOSSIBLE for a bad CAS to create an intermittent start issue. (A bad CAS will also not stop a running car.) Tell them you insist they do a PUMA for this and give you WRITTEN confirmation from BMWAG. DO NOT BELIEVE WHAT THEY SAY.



3. You need someone to look into your high pressure fuel pump. Is the fuel pump working? Is it generating the required pressures and holding this????




edit...OP is in Australia. BMW dealers are bad, but really bad the further from Germany you get..... in the US, their diesel service is horrific. Maybe in Oz it is slightly better? But they are bad. My guess is they have a car that wont start, and are only focusing on this.

Appreciate the feedback from everyone. I thought a bad CAS wouldn't stop a car in its tracks (plus I don't have CAS).

I've had very little to do with BMW dealers in the past and assumed they'd plug in their diagnostics and know exactly what the issue was. Considering how many diesel BMW's are sold in Aus, you'd expect them to decent.

I'll follow up with the dealer today after they get back to me with a quote. I'm hoping they surprise me today with better news, but not holding my breath.

Do all dealers not do module coding at all and just order new units directly from Germany?

I'll post back with any updates.

Thanks!

In 1988, I drove my 323i to Scotland to take a new job there and had an overheating problem on the way. Dealer in Aberdeen claimed the radiator was SURE to be the problem..... They replaced it. I picked it up and within 5 miles the car overheated! Drove it straight back and they removed the new radiator, handed me my money back. Needless to say I was very unhappy. Took it home, found a specialist who assured me the head was cracked. I took the head off, had it welded, stress relieved and planed. Never overheated again :-). So, that was over 30 years back and much closer to Germany, taught me to fear all dealers.

A CAS may have to be programmed from the factory due to it being part of the security system on the vehicle but I'm not sure.

Agree- I dont think the CAS should stop a running car.




What makes you say you do not have CAS? Are you equating CAS=Comfort Access? I dont think this is accurate, google around for the pdf on comfort access and CAS. The "car Access System" is much broader than just reading key fobs.



BMW dealers DO NOT do coding. They buy a 'virgin' CAS, which will then accept a marriage to your cars VIN. Smart coders find this hilarious....


I could see the car- after a failed fuel pump, and they run the battery down, the CAS loses EWS sync and they become preoccupied with that...just a WAG.





and finally recognize diesel BMWs are pretty popular outside of USA. But still, its not in their DNA it seems.


GL!

Thanks for the info. They said it was an issue with the "comfort access" system, but perhaps they meant to say "car access", hence the confusion.

From what I can tell, a failed CAS module would cause the no start condition.

I found the attached doc which explained it well for me. I'll see what they say today. I might see if they can reset the CAS and realign with the DDE, before throwing big $$$ at it.

Surely there would be ECU errors from the DDE or other modules at fault? Modern car systems are quite good at noting out of the ordinary scenarios, e.g. lack of fuel rail pressure while engine is running. The Dealer's first port of call should be the fault memory.....

You plugged in your basic OBDII scanner which has zero of the bmw specific fault codes. Either ask the dealer for the fault codes and report back, or get a copy of ISTA D and scan it yourself.


Without those codes, you are a blind man walking around in a pitch black night