SCR NOx Catalyst Efficiency Below Threshold (Bank 1)
The BOBCAT-P20EE (Bobcat) diesel fault code means: SCR NOx Catalyst Efficiency Below Threshold (Bank 1). This is a serious severity code.
Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.
- Keep driving?
- Limited driving only
- DIY difficulty
- advanced
- Estimated cost
- $300-$3,500
What Are the Symptoms of BOBCAT-P20EE?
- Derate warning / 3-stage inducement countdown
- CEL and DEF lamp
What Causes BOBCAT-P20EE? (Most Likely First)
- Contaminated DEF fluid (wrong fluid / water) Likely
- Failed downstream NOx sensor Likely
- Plugged / aged SCR catalyst Possible
Can I Still Drive with BOBCAT-P20EE?
Limited driving only. BOBCAT-P20EE is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What is Bobcat code P20EE?
Bobcat P20EE: SCR NOx Catalyst Efficiency Below Threshold (Bank 1). This code is reported on Bobcat equipment running the described engine family.
Can I keep working with Bobcat code P20EE?
Limited operation only -- finish the current task then shut down for repair.
How much does Bobcat P20EE cost to fix?
Estimated repair cost: $300-$3,500. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Bobcat Service Analyzer) is usually required.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose BOBCAT-P20EE?
Test DEF fluid with refractometer (32.5% urea).
Scan NOx sensor outputs upstream/downstream during load.
Check SCR inlet NH3 dosing via Service Analyzer.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P20EE as a generic OBD-II code)
P20EE on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
Which Vehicles Commonly Get BOBCAT-P20EE?
- Bobcat S650 skid steer loader (Kubota V3800)
- Bobcat S740 / S750 / S770 / S850 skid steer loaders (Kubota V3800)
- Bobcat T650 / T750 / T770 / T870 compact track loaders (Kubota V3800)
- Bobcat E50 / E55 / E60 / E85 mini excavators (Kubota V3800)
- Bobcat UW56 utility vehicle (Kubota V3800)
Explore More
Was this helpful?
Send this to whoever is fixing the truck — your tech, or the person asking what the fault means.