SubZero Refrigerator Freezer Error Code 40 – How to fix? by KatyApplianceRepair.com 

Sub-Zero error code EC 40 indicates
excessive freezer compressor run time. Below is a quick reference
and troubleshooting guide for this code.

Quick Reference

Error Code	Meaning	Severity
EC 40	Excessive freezer compressor run — freezer not reaching set temperature efficiently	Medium

Cause & Solution

Cause	What to Check	Fix
Dirty condenser restricting airflow	Inspect and clean the condenser coils	Vacuum or brush the condenser; ensure kick plate is not blocked by cabinetry
Door left open or gasket leak	Check door seal alignment	Replace gasket if damaged; clear error by holding door-ajar alarm key 15 seconds