299D3 XE: catalyst reagent concentration low

[Ric.M]

New 299D3 owner, new to DEF.

Received 3516-18 code, “Catalyst Reagent Concentration Low-Moderate Severity”

just received my machine (used, 2020). I know it’s been mosty sitting for at least 6 months, so plausible that the DEF has deteriorated in the tank.

DEF level shows >50% on the gauge so I figured first step is to drain existing DEF and replace with new. I bought a hand siphons pump from Harbor Freight which has ~36” inlet hose. Was able to get that about halfway into the DEF tank before hitting solid resistance (feels like hose is hitting the bottom of the tank). I backed it off a little and started pumping to start the siphon but no luck, just getting air. Retried several times, same result.

is there a better way to drain the DEF tank, or perhaps a better way to address this issue?

Thanks in advance…

 

[heymccall]

First off, test the DEF. A refractometer is used. Not very expensive.

 

[Ric.M]

First off, test the DEF. A refractometer is used. Not very expensive.

well, that’s the rub… I bought an inexpensive refractometer, but I’m unable to draw DEF from the fill port for testing. I tried the Harbor Freight siphon pump with a larger ~5/8” tube and failing there, I purchased a second siphon pump from Amazon with a ~3/8” tube. Both go in approx 18” and hit resistance which feels like the bottom. Both siphon tubes come out completely dry so no evidence that they reached liquid.

thinking maybe the fill sensor had failed (and the tank was in fact empty), I added ~2 gal DEF to make certain there was fluid in the tank. Gauge now reads nearly full and tube goes down just as far and again comes out dry. I was hoping this would at least increase the concentration of DEF eliminating the error, but no. Error returned shortly after running the machine today.

??? Is there another way to extract DEF for testing or drain the DEF tank?

 

[heymccall]

 

[heymccall]

 

[Ric.M]

Thank you, heymccall. Exactly what I was looking for!

 

[Ric.M]

Update: collected a sample for testing, drained the DEF and put a half-tank (2.5g) of fresh DEF in. That cleared the code.

Thanks to the community (especially heymccall) for this resource. I couldn’t find a single video on YouTube that walked through draining the DEF reservoir. I can clearly see, after lifting the cab, why siphoning from the fill didn’t work - there’s a 3 foot hose with a couple hard-90’s that snakes to the front of the belly pan where the DEF tank is located.