What is Komatsu Code E15 CA553 & How to Solve It?

What is Komatsu Code E15 CA553:

This fault refers to a regeneration-related failure, typically pointing to a malfunction in the DPF temperature or pressure sensor.

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Why This Happens

• Failed or stuck DPF temperature or pressure sensor.
• Incomplete or failed regen cycles.
• Abnormal exhaust flow or backpressure.
• Soot buildup or exhaust restriction.

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How to Fix It

1. Inspect temperature and pressure sensors around the DPF.
2. Replace any sensor that reports unrealistic values.
3. Perform a manual regen using OEM diagnostic software.
4. Clear the code and confirm soot levels return to normal.

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How to Avoid It Before It Happens

1. Run regen cycles regularly without interruption.
2. Track DPF health and soot accumulation over time.
3. Replace aged sensors based on runtime history.