Indoor Heat Exchanger Temperature Sensor Error

What it means

This code appears on Toshiba residential split air conditioners when the fault code is read with the remote check function. It means the indoor coil (heat exchanger) thermistor, TC, is open or shorted. The unit relies on this sensor to protect the coil from freezing and to control the fan, so it stops when the reading is lost. The same code can mean something else on other brands, and Toshiba commercial units use different codes.

Models covered: Toshiba residential split air conditioners (RAC) that show a two-character check code through the remote check function; Toshiba commercial units use different codes.

Related codes: 0C1112

Symptoms4

• The unit stops and the indoor unit lamps blink.
• Code 0D is found with the remote check function.
• Ice on the coil or weak cooling before the stop in some cases.
• The fault appears after the coil was washed or the indoor unit was opened.

Possible causes5

• The sensor has slipped off the coil pipe or its connector is loose.
• The thermistor has failed from constant moisture around the coil.
• The sensor lead was cut or pinched during service.
• Corrosion at the connector from condensate or wash water.
• A fault in the sensor input circuit on the indoor board.

How to diagnose5

1. Read the code with the remote check function: press and hold the check button, then step through the codes with the timer button until the indoor unit beeps continuously; the code shown then is the fault. Steps vary slightly by remote, so follow the owner's manual.
2. Switch off at the breaker for a few minutes, restart and note when the code returns.
3. With power off, the technician confirms the sensor is seated on the coil and its connector is dry and sound.
4. The technician measures the sensor resistance against the manufacturer table, flexing the lead to catch an intermittent break.
5. If the sensor is good and the code stays, the indoor control board is checked.

How to fix5

1. Refit the sensor on the pipe and secure it well.
2. Dry and clean the connector or repair the lead.
3. Replace the coil thermistor with the correct part for the model.
4. Replace the indoor control board if proven faulty.
5. Run in cooling long enough and confirm the code does not return.

Repair cost

In Saudi riyals; the highlighted part is the expected range for this fault.

The cost stays low for a connector repair or new thermistor, and rises if the indoor control board must be replaced.

Prices are rough estimates including the part and the technician’s fee, and vary with brand, model and part source.
Prices last updated: September 2026

Frequently asked questions