Fix Fujitsu PrintPartner V40 E21 Error | Fuser Warmup
Error code E21 on the Fujitsu PrintPartner V40 occurs when the fuser heater fails to attain its operational temperature within the required warm-up period. The printer triggers a hardware lockout to prevent improper toner fixing and safety hazards.
Common causes
- 1Unstable AC mains line voltage.
- 2Fuser thermistor coated in dust or out of calibration.
- 3Blown thermal cutoff fuse in the fuser unit.
- 4Defective heating element or lamp.
Solutions
Troubleshooting Code E21
This temperature fault protects internal heat rollers from electrical anomalies.
Recommended Actions:
- Power Cycle Reset: Switch off the printer and unplug the power cord for 10 minutes to reset the fuser monitoring circuits.
- Wall Outlet Direct: Plug the power lead directly into a wall socket, bypassing power strips or backup UPS units that may limit current.
- Power On Test: Turn the device on and monitor the initial warm-up sequence.
Steps to follow
- 1
Unplug from power outlet
Turn off the main switch and pull the plug out of the electrical socket.
- 2
Allow unit cool down
Wait 10 minutes for internal heat sensors and capacitors to reset.
- 3
Plug directly to wall socket
Reconnect the cable straight into a dedicated wall outlet and turn on.
Videos
Frequently asked questions
Not always. A low voltage drop during startup can cause a false E21 error that clears with a proper power reset.
Waiting 10 minutes allows the logic board to properly discharge and recalibrate the thermistor values.