C-A2 Moderate Moderate DIY

Samsung Microwave C-A2 — Humidity Sensor Short Circuit

Samsung Microwave · Error code C-A2

What C-A2 Means

Humidity sensor reads as shorted. Sensor-based cycles disabled.

Symptoms

  • C-A2 displayed
  • Sensor Cook unavailable
  • Microwave otherwise runs on Time Cook

Common Causes

1
Shorted humidity sensor

Internal sensor element failed shorted.

2
Pinched/melted sensor wire

Wire chafed and shorted to chassis.

3
Moisture intrusion at sensor connector

Steam wicked into the connector and bridged pins.

4
Main PCB input fault

Less common.

How to Fix It

  1. Unplug and let the unit dry for several hours if recent steamy cooking is suspected.
  2. Inspect and reseat the humidity sensor connector.
  3. Ohm the sensor — a near-zero reading confirms a short.
  4. Replace the humidity sensor with the OEM part.
  5. Inspect harness for melted insulation; repair or replace as needed.

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.

Common replacement Samsung microwave humidity sensor View on Amazon→

More Samsung Microwave Codes

-dr- -dr- — Door Open (Demo / Reminder) 5E 5E / SE — Touchpad Shorted (Older Spelling) C-21 C-21 — Cavity Over-Temperature C-22 C-22 — Cavity Thermistor Open C-A0 C-A0 — Communication Error Between Boards C-A1 C-A1 — Humidity Sensor Open Circuit

All Samsung codes → All microwave codes →

Verified against manufacturer documentation: samsung.com

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician.