XC90 AdBlue error

[Ahtif]

Hi,

I have a 2018 year XC90 with a D5 173kW engine.

Yesterday, the engine light came on, and the fault code reader says an empty AdBlue tank error. In reality, it is not empty, around 75% full.
Does it mean that the level sensor is dying, and I need to replace the whole tank?

Is it a DIY job, or need to visit the dealer? How hard it could be to remove the tank?

Thanks in advance.

[nu11eaf]

Have tried adding a bit more ad-blue and seeing if the fault code resets, level sensor may be crudded up and showing a false high level.

[togvolvo]

In addition to amber(?) engine warning light.
Was the message "Ad blue service required, circa 500 miles to no start"?
I first got this message after heavy braking/turning left into a side road.
Dealer advised top up ad blue (even though 90% full).
Fill the fuel tank with diesel.
All warnings disappeared with 2 days/2 or 3 engine starts.

(An amber engine light meantime cured by an exhaust temperature sensor change- unrelated, who knows?)

This occurred a couple of times over a few months and this procedure worked each time.
Following an ad blue injector cleaning at a service visit...the blue message & light came on the way home!

Did same clearance top ups again..
Called dealer, nothing could be done until lights came on again to allow a fault log check.
Car traded before 'glitch' resolved.

[SnineT]

It's not going to help you this time but I advocate you never let it get below 3 bars and never fill more than 2 bars from maximum and squeeze the pump slowly if using a petrol station pump to top it up.

No straining the system and no packing it in either.

[OldEngineer]

This is a well known problem for Mercedes owners with many experiencing the error of 500 miles to no start. Some is about the quality of the AdBlue product. For others it is a substance on the AdBlue pump outlet
But most find it impossible to reset the system without a code reader and invoking a 'Relearn' function.

Those that don't suffer seem to be the owners who don't buy cheap AdBlue and don't allow the reservoir to go too low.

[Adam1961]

Originally Posted by Ahtif

Hi,

I have a 2018 year XC90 with a D5 173kW engine.

Yesterday, the engine light came on, and the fault code reader says an empty AdBlue tank error. In reality, it is not empty, around 75% full.
Does it mean that the level sensor is dying, and I need to replace the whole tank?

Is it a DIY job, or need to visit the dealer? How hard it could be to remove the tank?

Thanks in advance.

Hiya,

Did you get any other codes? Normally an EML won't be caused by the low adblu message, but something else.

I wonder if you've got a P20EE00 code or something similar for the NOX CAT, as this one is adblu related and causes the EML to come on. Normally this code will be stored if the rear NOX CAT is cracked, which can be caused by another fault, like an air leak.

Hope this helps!

[S60inFrance]

Could be worth checking the nozzle attached to the exhaust where the adblue is squirted in. They can block up and cause the system to think the tank is empty. It's just like limescale build up and quite surprising. You can Google it to see what I mean!