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error DeWalt

Error Code 34

Incorrect oil usage — wrong type or grade of oil has been used in the pump.

? What Causes This

Using oil that does not meet DeWalt specifications or using engine oil instead of pump oil.

How to Fix It

  1. Drain the incorrect oil completely.
  2. Refill with the correct pump oil as specified in the manual.
  3. Consult the manual for proper oil type and grade recommendations.

Source: page 6 of the official manual

From the manual

Manual page 6 — DeWalt error 34

This error code appears in:

DeWalt 3300 Psi Pressure Washer