BOBCAT-P20E8 serious Bobcat ›

Reductant Pressure Too Low

The BOBCAT-P20E8 (Bobcat) diesel fault code means: Reductant Pressure Too Low. This is a serious severity code.

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Keep driving?
Limited driving only
DIY difficulty
advanced
Estimated cost
$500-$1,800
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Common Symptoms

  • DEF dosing fault / lamp on
  • Derate active or pending

Probable Causes (Ranked by Likelihood)

  • Failed DEF supply module (pump) Likely
  • Frozen / crystallized DEF in supply line Possible
  • DEF filter restricted Possible

Frequently Asked Questions

What is Bobcat code P20E8?

Bobcat P20E8: Reductant Pressure Too Low. This code is reported on Bobcat equipment running the described engine family.

Can I keep working with Bobcat code P20E8?

Limited operation only -- finish the current task then shut down for repair.

How much does Bobcat P20E8 cost to fix?

Estimated repair cost: $500-$1,800. 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

Step-by-Step Diagnostic Procedure

  1. Scan DEF pressure during purge cycle.

  2. Inspect DEF heater circuit fuse and relay.

  3. Replace DEF supply module if pressure cannot build.

Sources 1

This page is built from documented references. Verify against your own service info before repair work.

  • SAE J2012Diagnostic Trouble Code Definitions (defines P20E8 as a generic OBD-II code)

P20E8 on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

Hino serious Reductant (DEF) Pressure Too Low Isuzu serious Reductant (DEF) Pressure Too Low Kubota serious Reductant Pressure Too Low PACCAR serious Reductant Pressure Too Low Yanmar serious Reductant Pressure Too Low

Commonly Affected Vehicles

  • 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)

Related Codes

BOBCAT-P20EE

Explore More

More Bobcat codes → Diesel home All diesel codes Heavy-duty Guides

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