E4
DeWalt Motor Control / PWM Driver Fault

Vacuum runs only at low speed or surges; E4 code or flashing pattern on speed/charge indicator

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Failed MOSFET on control PCB, Damaged speed control trigger, Shorted motor windings, Corroded wiring harness connector

How to Fix / Troubleshooting

Safety: Remove the battery and discharge any static before opening the housing. If you are not comfortable with electronics, seek professional service.

  • External checks first: Confirm filters and airflow are normal to rule out overload. Try another battery to exclude low-voltage issues.
  • Inspect trigger mechanism: Remove the handle cover (if serviceable) and check the trigger switch for physical damage, contamination, or loose wires.
  • Check wiring harness: Look for burnt, pinched, or disconnected wires between the trigger, control PCB, and motor.
  • PCB inspection: Examine the control board for burnt components, cracked solder joints, or corrosion. Do not touch components with power applied.
  • Resolution: In most cases, the entire control PCB or motor/control module must be replaced as a unit. Order the correct DeWalt control board for your model.
Advertisements

Repair Difficulty

Professional Required 5/5

Required Part

Motor Control PCB
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements