LG · Dishwasher
LG Dishwasher PE Error Code
Water level pressure sensor fault
What this error means
PE is a Pressure Error—the water level sensor did not provide a valid signal during fill or drain transitions.
How PE is detected
When PE appears on a LG dishwasher, the control board has confirmed that water did not leave the machine within the programmed drain window. On LG LDF5545ST, LG LDP6797ST, and similar variants, the drain pump runs for a fixed interval—often three to seven minutes on washers and dishwashers—while a pressure switch or turbidity sensor verifies the tub or sump is empty. If water remains, the cycle stops to prevent spin with a full tub or overflow on the next fill.
Most PE calls are resolved without parts: power off and trace the thin hose from the tub to the pressure switch. Restricted drain paths mimic pump failure because the impeller spins against a blocked hose or filter. Document whether the pump hums audibly during the drain step; a humming pump with no water movement points to a clogged filter or kinked hose, while silence may indicate a failed pump motor or loose wiring at the harness.
After clearing blockages, run a short cycle and listen at the drain hose for steady water flow. If PE returns on the next load with a clean filter and straight hose, measure resistance at the pump motor connector per the service manual for your model before ordering a replacement pump assembly.
Common causes
- Air chamber hose disconnected from the tub
- Pressure switch clogged with detergent slime
- Loose connector at the main board
- Split hose letting air escape without tub pressure change
Step-by-step fixes
- 1Power off and trace the thin hose from the tub to the pressure switch
- 2Blow through the hose—it should be unobstructed
- 3Reattach firmly at both ends
- 4Run a fill test and watch whether water stops at the correct height
When to call a technician
Intact hose with persistent PE requires pressure switch or board replacement.
Affected models
- LG LDF5545ST
- LG LDP6797ST
- LG LDTS5552S
Prevention & maintenance
- Clean drain filters and hose terminations monthly on high-use dishwashers to prevent PE from lint and food debris buildup.
- Record when PE appears in the cycle and whether it clears after a 60-second power reset on your LG dishwasher—that detail speeds diagnosis if you call service.
- Keep the model and serial number from the rating plate when ordering parts for PE; LG uses multiple revisions with different harness lengths and board firmware.
- Photograph wiring connector orientation before disconnecting any component while troubleshooting PE; reversed plugs on pumps and valves cause immediate repeat faults.