EC53 outdoor ambient temperature sensor fault

What the control is telling you

The outdoor board reads the outdoor ambient temperature sensor (T4) as open or shorted. Manual gives the meaning only; steps are standard sensor checks.

Applies to: DLCURAH18-60 AAK/ABK single-zone heat pump outdoor units (18K-60K, regular and High Heat)

Likely causes

• Sensor connector loose or unplugged on outdoor board
• Damaged sensor wire
• Failed sensor
• Outdoor main board input fault

Test and repair steps

1. Warning: Turn off and lock out power at the outdoor disconnect and wait for the inverter capacitors to discharge before touching the outdoor board or compressor wiring.
2. Check the indoor unit display code first - the manual says indoor codes often point to the outdoor problem; see the service manual for detailed tests.
3. Find the outdoor ambient temperature sensor plug on the outdoor main board and reseat it.
4. Inspect the sensor lead for cuts, chafing or crushed sections.
5. Unplug the sensor and check it for open or short circuit with an ohmmeter (compare to the service manual resistance chart).
6. Replace the sensor if open/shorted; if the sensor checks good, suspect the outdoor main board.

Settings for these units

Outdoor unit minimum clearances · Midea DLCURA ducted single-zone inverter heat pump (outdoor)

Side letters taken from Fig. 8 drawing.

Units facing each other: 59 in. (150 cm) or more; do not blow into another unit's inlet.

Models that show this code

12 models in Midea DLCURA ducted single-zone inverter heat pump (outdoor)

Other codes on the same units

• EC07 Outdoor DC fan motor fault / speed out of control
• EC50 outdoor temperature sensor fault
• EC51 Outdoor EEPROM error
• EC52 condenser coil temperature sensor fault
• EC54 Discharge temperature sensor (TP) open/short
• EC57 refrigerant pipe temperature sensor fault
• EC71 Outdoor DC fan motor over-current
• EC72 Outdoor DC fan motor lack-phase