DEF Notification CEL

2015 Passat TDI SE, 123,000

Friday the DEF notification came on 600 miles before no start. I just recently had the oil changed so logically I figured the dealership forgot to top off the DEF fluid. Stopped in Saturday to have it topped. Notification never came on Sunday.

Now yesterday Monday, it's back 500 in range and now accompanied by a CEL. I did a bit of research in the forums and came across a few items, possible NOX sensor, possible DEF heater etc....

Does anyone have a few suggestions in diagnosing and repairing this annoyance without having it expire, towed to the dealer and pay a big chunk of change.

Thanks in Advance for your assistance.

Stop creating a new thread every hour. This is your thrid thread for the same thing.

I already replied in one of your threads.

Fixmy59bug said:

Stop creating a new thread every hour. This is your thrid thread for the same thing.

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+1. Chill.

But DEF - it's not refilled automatically at oil changes, unless you're paying separately for it. My suggestion would be to buy a few gallons of DEF (or refill at a gas station, anymore DEF is right at the pump) and try to refill. If they only put a plug or two into the tank because you brought it back, it's not enough to reset the level sensor, and you are likely low.

If the tank accepts more than a few squirts, I suspect you've found your issue. If not, schedule an appointment with the dealer to have it looked at under the emissions warranty. If it is truly a fault of the system, it's covered by VW.