Good news for those experiencing the P203A code (Diesel models). I Have been getting sporadic CEL since May. I'm out of factory warranty (2010 X5D, 56K miles). Since CEL doesn't stay on for long, I kept putting the dealer visit off until I could take it in while CEL was on. Well, that never happened. Finally decided to take the car in even though CEL turned off after the last episode. I double checked to make sure there was a stored error before going in. Long story short, dealer is covering it under CA emissions warranty 7 years/70K miles. As others have stated, the issue is a malfunctioning DEF Active tank sensor. It's on back order and I am supposed to check back in a week. This is great news for all you out of warranty Diesel X5ers who are getting this error in CA emission states.

Work order attached.

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