35D DEF Tank Level Sensor Issue
 

2011 35D with 98K miles, 3rd party extended warranty. Engine warning light comes on and we take it in. After 5 days (including weekend) the diagnosis is the DEF tank level sensor is bad. Part in Germany. 1-2 weeks. $1,800 with a 20% discount for good customer. Says we can't drive it because the engine may shut down at anytime if it doesn't sense the DEF.

Well 5 weeks later, still no part. SA claims BMW holding up diesel parts or anything to do with diesel repairs due to the clamor over the VW diesel emissions issue. I find this hard to believe, but we are still out of our car which will be paid off next month.

They gave us a 2016 X3 3.5 with 23 miles on it as a loaner. Now has 2,340 miles on it. We are allowed 100 miles a day. Told us to keep it until the repair is complete. Nice SAV. Very quick. Love the exhaust note at shift under hard acceleration!

The DEF tank delay/backlog did exist before Dieselgate broke, but there have been reports also from before dieselgate that the DEF tanks were being delivered.

Seems these DEF tanks are starting to have a lot of problems and they are not cheap and do not appear to be easy to access/install.

Temp and level sensors, not sure if they are one in the same?

Not sure I would be standing in line for a Diesel anything. I have stayed away from them for this long, why take on these headaches now?

Both OPie and I have diesels. I have had diesel automobiles since 2000, two VWs and now BMW

I assume that BMW does not have enough inventory for these DEF tanks because they are failing at a much higher rate than they expected AND/OR they may be redesigning some of the sensors do to the high failure rate.

So it appears these tanks have temperature sensors, level sensors and a heater from what I gather.

Here is a picture of the tank with some of the senors.

https://www.ecstuning.com/ES254461/

I have passed on Diesels for my vehicles and I am not no hurry to get in line.

These diesels have their downsides, but honestly, I will take it anyday over the N62 and N63. N52 and N55 seems to fare much better.
My diesel has faulty DEF transfer pump, but instead of spending $400 i just keep adding DEF to the active tank every 2-3 k miles.
I visited a shop yesterday that are fixing '12 X5D with a broken active tank. I have to take a better look at it and take some pictures.

Ah, now I see, there are actually 2 tanks!!! Both not cheap and I assume both not so easy to access?

Would be interesting to see what tanks are having more problems.

I assume the OP is waiting on the Active DEF tank? Seems like more DEF tank problems are likely to start popping up in the near future.

I think everyone needs to be clear on what tank they are having problems with.

Oh what fun!

Passive tank failures are very rare. There is only 1 sensor inside.
Once we find a solution for adding external active tank temp sensor replace rate will go down 60-70% from whom is interested in DIY. Level sensor failures, like OPs, are much rare. But there must be a way to emulate this signal.
Last resort would be to disable the DEF in DDE(VW did it in a corporate level :stickpoke) or disable the DEF related codes. These solution will come soon as more and more diesels are going out of warranty and there will be a real demand. In the same way as replacing the dreaded N62 coolant transfer pipe was $6-8k years ago and now is offered for under a grand in many places.

I proactively installed a Bimmer Fix | Coolant Pipe Repair System coolant sleeve in my N62 when I replaced the water pump a few weeks ago for $200.

So hopefully I will not have to deal with a leaking coolant transfer pipe in my N62 during my ownership!

But there seems like a market will quickly pop up for DEF tank solutions.

Is there a transfer pump between the passive and active tank? I did not see one listed, but I did not spend a lot of time looking at the system since I do not have a Diesel. But I was just curious as to what/how the temp sensor functions and if there was a work around other than replacing the entire tank at great expense.

Wondering how much they charge? Here is another company fixing bmw def tanks for fixed 499.