What causes the Sd code on a LG washer?

Wrong detergent type: Non-HE detergent in an HE-only washer — 90% of Sd cases. Over-dosing HE detergent: Even correct detergent makes excess foam if you dose past the line. Soft water or low load: Soft water and small loads need much less detergent.

LG · Washer Minor

Sd — Suds detected (suds-reducing routine running)

Sd on WashTower and newer-firmware LG washers means the same thing as Sud — too much foam detected, so the unit is running its ~2-hour suds-reduction routine. Not a hardware fault if it clears.

Keep using it?: Yes — fix when convenient
DIY difficulty: Easy
Verified against: lg.com ↗

How to fix it

Let the suds-reduction routine finish — do not interrupt unless leaking.
Going forward, use HE detergent only at 1-2 tablespoons per normal load.
Pull the dispenser drawer and rinse under hot water; brush out the back recess.
Open the lower drain pump filter and clear lint over a shallow pan.
Run an empty Tub Clean cycle with washing machine cleaner.
For soft-water homes, cut detergent dose in half.
If Sd reappears with the correct dose of HE detergent, suspect the pressure sensor.

Why it happens

Typical signs: Sd on the display · Cycle time extends by hours · Heavy foam visible in the door · Extra rinses being added

Wrong detergent type Non-HE detergent in an HE-only washer — 90% of Sd cases.
Over-dosing HE detergent Even correct detergent makes excess foam if you dose past the line.
Soft water or low load Soft water and small loads need much less detergent.
Detergent buildup in tub Years of over-dosing leave residue that keeps releasing foam.
Slow drain or clogged pump filter Soapy water hangs around, keeping suds high.

Parts you may need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

Washing machine cleaner Common replacement
Amazon →
Pressure sensor Common replacement
Amazon →

More LG washer codes

AE AE — Leak / auto shut-off (base pan water detected) CE CE — Overcurrent Error CL CL — Child Lock Is On dE dE / dE1 / dE2 Error — Door Will Not Lock dE1 dE1 — Door not fully closed dE2 dE2 — Door closed but won't lock

All LG codes → All washer codes →

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: lg.com.