LG · Washing Machine
LG Washing Machine PF Error Code
Power interrupted mid-cycle
What this error means
PF is a Power Failure code—not a component fault. The control board lost AC power during a cycle from a tripped breaker, brief outage, or someone unplugging the unit. LG stores enough state to offer resume on some models.
How PF is detected
LG washing machine models lock the door or lid before energizing fill, heat, or high-speed spin. PF means the latch switch never sent a "locked" signal to the main control, or the lock motor did not complete its travel. On LG WM3400CW, LG WM3900HWA, and similar variants, clothing caught in the gasket, a misaligned strike, or a failed latch assembly are the most common mechanical causes—not the board itself.
Inspect the door gasket perimeter and strike alignment before replacing the latch. Tripped circuit breaker or blown fuse on the laundry circuit is reported frequently on this code. After correcting mechanical issues, check the breaker panel and reset any tripped laundry-room circuit. If the latch clicks but PF persists, the door lock switch or wiring harness to the control board likely needs testing with a multimeter.
Do not force the door open during an active cycle; wait for the lock to release when the board de-energizes the lock motor—usually two to three minutes after canceling power on most LG units.
Common causes
- Tripped circuit breaker or blown fuse on the laundry circuit
- Loose power cord at the outlet or terminal block
- Brief neighborhood power outage during the cycle
- Using an extension cord that cannot sustain motor start current
Step-by-step fixes
- 1Check the breaker panel and reset any tripped laundry-room circuit
- 2Press Start—many LG models offer Resume if power returned within a few minutes
- 3If water sits in the tub, run Drain + Spin before restarting the full cycle
- 4Plug directly into a grounded 120V outlet rated for 15A—avoid extension cords
When to call a technician
If PF appears while other appliances on the same circuit work fine, inspect the washer power cord and terminal block for heat damage.
Affected models
- LG WM3400CW
- LG WM3900HWA
- LG WT7300CW
Prevention & maintenance
- Wipe the door gasket weekly and avoid overloading items against the seal—PF often starts as a slow leak or latch misalignment.
- Record when PF appears in the cycle and whether it clears after a 60-second power reset on your LG washing machine—that detail speeds diagnosis if you call service.
- Keep the model and serial number from the rating plate when ordering parts for PF; LG uses multiple revisions with different harness lengths and board firmware.
- Photograph wiring connector orientation before disconnecting any component while troubleshooting PF; reversed plugs on pumps and valves cause immediate repeat faults.