Carrier Error Code 44: Blower Motor Communication Fault (Meaning, Causes, Fixes)
What the code means
Carrier's Residential Fault Code List (Technical Information TIC2025-0010) lists 44 as an indoor-unit code: "Cannot communicate with blower." On a communicating fan coil such as the FE4A or FE5A, the fan coil control talks to the ECM blower motor at least once every five seconds, even when the motor is idle. If the motor doesn't acknowledge those messages, the control flashes Status Code 44 on its amber STATUS LED (4 short flashes, then 4 long flashes) and keeps trying. As soon as the motor answers again, the code clears on its own. Carrier's service instructions add that if the motor goes more than 25 seconds without hearing from the control during operation, it shuts itself down and waits. Carrier's Infinity/Evolution troubleshooting guide shows 44 as BLWR COM FAULT in the fault history and, on most software versions, as CRITICAL MALFUNCTION, CALL TECHNICIAN on the main screen, with the mode LEDs alternately flashing. Code 41 (Blower Motor Fault) is the related code for a motor that talks to the board but won't come up to speed. Don't confuse indoor 44 with outdoor code 44-13 (PEV Timeout), which is a different fault on the same list.
Likely causes
- A loose, unplugged or damaged low-voltage motor harness between the fan coil control and the ECM motor. Carrier tells you to check that both ends are seated and that every wire makes a complete circuit and isn't shorted.
- No 12-volt DC supply to the motor from the control board (pins 1 and 2 of the motor header). If it's missing, Carrier says to replace the circuit board.
- A failed control module on the ECM motor. If the harness and the 12-volt supply check out, Carrier says the fan coil control is good and the motor's control module may need replacing.
- A failed fan coil control board that can't send the signal, shown by the MOTOR LED not flashing during Carrier's test even with 24 volts present.
- A motor that has lost its high-voltage power, which Carrier checks first at the motor power plug (240 volts on the FE4A).
- General HVAC background, not Carrier text: power surges and outages are a common time for ECM motor electronics to fail, so 44 after a storm points toward the motor module.
Safe DIY checks
Turn off power at the furnace/HVAC service switch and the breaker before opening panels.
- Write down what the thermostat (wall control) says, such as BLWR COM FAULT or Critical Malfunction, and whether code 41 is also in the fault history.
- Turn power to the indoor unit off at its breaker or disconnect, wait a few minutes, and turn it back on. If the motor answers the board again, Carrier says the code clears by itself.
- Look through the indoor unit's sight glass or at the board for the amber STATUS LED. Four short flashes followed by four long flashes is code 44.
- With the power off, open the blower access panel and make sure the motor harness plugs are fully seated at both the control board and the motor. Look for chewed, pinched or burnt wires.
- Check the low-voltage fuse on the fan coil control. A blown fuse usually means a wiring short somewhere, so find that before replacing it.
- Don't open the motor's control module yourself. Carrier warns to wait at least 5 minutes after cutting power before removing it, because internal capacitors stay charged.
🛠 When to call a pro
- 44 comes back after a power cycle and the harness plugs are seated.
- A technician should follow Carrier's fan coil board test: with the ABCD and motor plug disconnected and R-G jumpered, the MOTOR LED should flash; then measure 12 volts DC across PL1-1 and PL1-2 and a steady 5 volts DC across PL1-3 and PL1-2.
- They should also confirm line voltage at the motor power plug and test the motor windings before replacing the control module, since Carrier says not to assume the motor is bad just because it won't start.
- If the board's supplies are good, the motor control module (or the whole ECM motor) usually needs replacing, and it must match the fan coil model so you don't get code 25.
- The system is under warranty. Call your Carrier or Bryant dealer rather than buying parts yourself.
Parts that commonly fix it
Always match the part number to your exact model.
Digital multimeter
For checking the 12-volt and 5-volt motor signals and line voltage. Leave high-voltage tests to a technician if you're not experienced.
Search eBay →ECM blower motor or motor control module
Match the part number on your motor and fan coil. Carrier sells the control module separately from the motor.
Search eBay →Replacement fan coil control board
Only if the board fails Carrier's 12-volt or MOTOR LED test. Match your board's part number.
Search eBay →Sources
- Carrier Technical Information TIC2025-0010, Residential Fault Code List (44 Indoor: Cannot communicate with blower; 44-13 Outdoor: PEV Timeout)
- Carrier FE4A/FE5A Communicating Fan Coil installation instructions (Status Code 44, Motor Communication Fault; STATUS and MOTOR LEDs)
- Carrier FB4, FE4, FH4, FV4, FX4 Residential Fan Coil Service and Maintenance Instructions (Status Code 44 steps and FE4A advanced board test; distributor-hosted copy)
- Carrier Infinity/Evolution Troubleshooting Guide, Rev. 2 (44 Motor Communication Fault, BLWR COM FAULT, Critical Malfunction; distributor-hosted copy)
Last reviewed 2026-10-25. Always confirm against the manual for your exact model number.