LG Washer PE Error Code: What It Means and How to Fix It

Updated · from manufacturer service documentation

The PE code on an LG washer means a Pressure Sensor Error — the sensor that reports water level to the control has failed a check. Per the service documentation, this is diagnosed through a short chain of checks: the connector, the sensor's resistance, and the air chamber/tube it relies on.

What Causes the PE Code

CauseLikelihoodDIY difficultyRelated part
Connector to the pressure sensor disconnected or disassembledMost commonEasy — reconnect connectorPressure sensor connector
Air chamber or tube clogged with foreign materialCommonEasy — clean air chamberAir chamber / tube
Pressure sensor resistance out of rangeLess commonModerate — multimeterPressure sensor
Main PCB assembly faultRarePro repairMain PCB

How to Fix the PE Error, Step by Step

  1. Check whether the connector to the pressure sensor is disconnected or disassembled

    If it is, reconnect or repair the connector — this is the first documented check for PE.

  2. Check the air chamber and tube for clogs

    Per the service documentation, a clogged air chamber or tube can produce a PE reading — clear any foreign material found.

  3. Test the pressure sensor's resistance

    Between pins 1 and 3, it should read 21–23 Ω (±10%). A reading outside that range means the pressure switch itself needs replacing.

  4. Read the pressure switch frequency in Test Mode, if PE recurs after the above

    A reading below 26.2 kHz while filling an empty washer also confirms a defective pressure switch on this platform.

  5. If everything above checks out, the Main PCB assembly may be at fault

    This is a job for a technician.

Which Models This Applies To

Documented for the LG WT5070C platform (Pressure Sensor Error flowchart with the 21–23 Ω resistance spec) and the LG top-load MFL40322141 platform (Test Mode frequency check, 26.2 kHz threshold). Per LG's training documentation for the WM0742HGA, PE (along with tE and dE) gets a shorter 20-second automatic shutoff timeout if not cleared, compared to 4 minutes for other error codes.

See also: LG washer dE · LG washer tE · Washer not filling.

Frequently Asked Questions

What does PE mean on an LG washer?

Pressure Sensor Error — the sensor reporting water level to the control has failed a check, most often traced to a disconnected connector or a clogged air chamber.

What resistance should the pressure sensor read?

Between pins 1 and 3, 21–23 Ω (±10%). Outside that range, the pressure switch itself needs replacing.

Could a clogged air chamber really cause PE?

Yes — it's explicitly listed as a documented cause, alongside a disconnected connector, before the sensor's own resistance is even tested.

How quickly does the washer shut off if PE isn't cleared?

Per LG's documentation, PE (along with tE and dE) triggers an automatic shutoff after just 20 seconds if not cleared, compared to 4 minutes for most other codes.

Based on the LG WT5070C service manual, the LG top-load service documentation (MFL40322141), and the WM0742HGA training manual. Last updated: .