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Old 11-18-2012, 10:05 AM
RPsX5d RPsX5d is offline
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Location: Bay Area California
Join Date: Nov 2010
Posts: 1,047
Mein Auto: X5 Diesel xDrive35d
Thanks for your post.

Not very familiar with these terminologies . . .
  • "pulling code" - this is printing out the *history* that is stored in the car - right? Related question - does the tech clear the history after the repair is finished or is the history permanent and not delete-able by the tech?
  • history is different from the listing of error codes generated - right? . . . error codes get deleted once the repair is performed - right?

Given I am not someone very familiar with all of these issues I have to go by logic . . . and my logic runs as follows:
  • Car was running just fine until the SCR Mixer and related programming work was done. (IMO the car would still be running just fine if this work was not performed)
  • I don't think the first NOx sensor replacemnt was necessary - i.e. I doubt it was really a defective sensor. That said, it is unclear to me why the 4D16-SCR didn't show up the first time
  • I was very surprised the catalyst had to be replaced - at 40,000+ miles, that is less than half the expected catalyst life - right?
  • One possible explanation for catalyst replacement - the new software has tighter specs than the old one, meaning the catalyst has to be more efficient . . . new catalyst has a different part number which could mean the catalyst material itself is different and its efficiency is sufficient (hopefully!) for the new software. Yes my logic is a bit of a stretch . . . if CEL doesn't back on I am happy to go with this logic!
I empathize with the tech - if he is pulling a fault code 4D16-SCR I am assuming he has to follow the solution dictated by BMW - right?

If I asked the dealer to "pull code" for me under a work order with the car showing no CEL or any other issues - who will pay for the labor? I doubt the dealer can make a warranty claim since the car is working fine . . . just curious.

Now if I have to go back in a third time for the same error code my scanner reads (P20EE) then I have a legitimate claim (IMO) to escalate this matter. I hate to beat up on folks who appear to be doing what they are expected/supposed to do.

As mentioned previously over the Thanksgiving period I am planning to put ~1,000+ miles - that should be a solid test to see if this latest fix holds.

Post Thanksgiving I will post whether I got the CEL or not.

PS: While trying to understand what 4D16-SCR I came across this post by ard and others . . . for those trying to understand this issue better, it is pretty good/quick read. Info is a bit dated - i.e. it may not apply to MY2011/12 cars . . . many fixes might already be in place.

Last edited by RPsX5d; 11-18-2012 at 10:09 AM.
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