Front-load washer and dryer pair in a home laundry room
8 components covered

Field manual · Washer

LG WM3400CW-series front-load washer: quick sheet

Covers: WM3400CW (white), 4.5 cu ft US rating (5.2 cu ft on Canadian pages); LG builder spec sheets dated 2022 and 2024 still list it. Introduced around 2018 (approximate).

Single sourceBrands: LG8 components

LG's best-selling entry 27-inch front-loader: Direct Drive motor, 6Motion, ColdWash, no steam generator. It shares the mechanical platform of LG 27-inch front-loaders, so parts and procedures carry over. Deep diagnostics: see the LG front-load direct-drive washer field service manual.

Safety first

  • Unplug the washer and shut both water taps before opening any panel.
  • Drain the tub (and the pump filter on front-loaders) into a shallow pan before pulling hoses; water may be hot.
  • Live-voltage checks at the control or valve connectors are caution work: insulated probes, one hand, no jewelry.
  • Get help lifting: these cabinets weigh well over 100 lb on the spec sheets.

How it works

The control locks the door, senses load size by turning the drum, and fills through the dispenser while reading the pressure sensor. 6Motion varies drum direction and speed for each cycle.

The Direct Drive rotor bolts to the drum shaft; the hall sensor on the stator reports position, which lets the inverter control start, reverse and ramp to the 1,300 rpm top spin.

If the drum cannot reach speed (overload, foreign object, motor fault) LG shows LE; unbalance shows UE and the control retries redistribution before giving up.

Components & tests

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Official manufacturer documentation

Always confirm values against the tech sheet for the exact model.

OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Front-load washer and dryer pair in a home laundry room by Curtis Adams, Pexels License

Diagnostic guides for this appliance

Component test · Washer

How to test a drain pump (washer and dishwasher)

Most drain pumps are small synchronous motors. Clear the filter and impeller first, then test the winding and the voltage. Published resistance values vary a lot by brand, so use the tech sheet for the number.

6 steps ~40 minmoderate
Component test · Washer

How to test a universal (brushed) motor and its carbon brushes

Universal motors run on AC or DC through carbon brushes that rub on a commutator. Brushes wear out and are the most common failure. Check brush length and the commutator, then test the field and armature with a meter.

6 steps ~60 minmoderate
Component test · Washer

How to test a top-load washer lid switch / lid lock

Older top-loaders use a simple lid switch; most newer ones use a lid lock with a switch and a locking solenoid or motor. Test the switch contacts with the lid open and closed, and check the lock coil if there is one.

6 steps ~20 minmoderate

Other washers manuals

Manual · Washer

Fisher & Paykel SmartDrive top-load washer: field service manual

Fisher & Paykel SmartDrive / Intuitive / Ecosmart top-loaders (e.g. GWL, WL, WA families). Older units report faults by beep pattern plus a binary pattern on the cycle LEDs; newer units have a numeric display.

6 components3 common failuresFisher & Paykel
Manual · Washer

Electrolux premium appliances: what differs from Frigidaire

Electrolux-branded front-load washers and dryers, French-door refrigerators and dishwashers sold in the US. Use together with the Frigidaire / Electrolux manuals in the washer, dryer, refrigerator and dishwasher sections.

2 components2 common failuresElectrolux
Manual · Washer

Compact & budget portable washers: field service manual

Portable and compact top-load washers (about 1.6-2.0 cu ft) that connect to a sink with a quick-connect adapter, plus simple twin-tub units.

3 components3 common failuresMagic Chef, Danby, Insignia, Other compact brands
LG WM3400CW-series front-load washer: quick sheet · OnCall Tech