Reductant Pressure Sensor Circuit
The KUBOTA-P204A (Kubota) diesel fault code means: Reductant Pressure Sensor Circuit. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- advanced
- Estimated cost
- $600-$1,800 supply module
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Common Symptoms
- MIL on
- No DEF dose, inducement
Probable Causes (Ranked by Likelihood)
- DEF pressure sensor harness corroded Likely
- Failed pressure sensor in supply module Possible
Step-by-Step Diagnostic Procedure
Back-probe sensor; check 5V/signal.
Replace supply module if internal failure.
Frequently Asked Questions
What is Kubota code P204A?
Kubota P204A means: Reductant Pressure Sensor Circuit. Serious code -- address promptly to avoid inducement / further damage.
Can I keep using my Kubota with P204A?
Serious fault -- you can move the machine to a shop but don't run it under load. Use Kubota Diagmaster software (dealer tool) for full diagnostics.
How much does P204A cost to fix on a Kubota?
Repair cost range: $600-$1,800 supply module. Compact-tractor labor is typically $110-$150/hr in 2026.