Error-code hub
Toshiba Carrier is the Toshiba and Carrier joint venture, and its systems use Toshiba's diagnostic scheme: a letter-plus-number code on the indoor unit or wired controller, with a check-code readout available through the remote. The 49 codes below come from Toshiba Carrier's own service literature and will look different from Carrier's own ductless range, which has separate pages here.
Unit applicability
This table is sourced for Toshiba Carrier 26 High Wall. If your unit is a different generation or product line not named here, the same display code may vary by generation.
Common codes first
Ranking basis: we do not have failure-frequency telemetry. These are ordered by breadth of affected systems in the SplitAtlas catalog - the documented product line's published model count, whether the same code appears on more than one product line, and any manual applicability notes we hold. This is a breadth ranking, not a popularity claim.
The Toshiba Carrier troubleshooting table lists E01 as no header remote controller. It points to incorrect remote controller setting, a header remote controller not being set, or no signal being received from the indoor unit.
The Toshiba Carrier table lists E02 as a remote controller transmission error. It says no signal can be sent to the indoor unit and lists system interconnection wires, the indoor PCB, and the remote controller as parts to check.
The Toshiba Carrier table lists E03 as an indoor unit to remote controller regular communication error. It says data is not being received from the remote controller or network adapter.
The Toshiba Carrier table lists E04 as an indoor unit to outdoor unit serial communication error. It points to the system interconnection wires, indoor PCB, and outdoor PCB.
The Toshiba Carrier table lists E08 as duplicated indoor addresses. It says the indoor address setting is wrong because the same address as the unit's own address was detected.
The Toshiba Carrier table lists E09 as duplicated header remote controllers. It says two remote controllers are set as header in double-remote control.
Safe first checks
These codes have homeowner-safe steps such as filters, airflow, condensate/drain checks, remote/controller items, or a single safe power reset. If the code returns, stop at the boundary in the card.
Power cycle the system once if you can do that safely. Do not change address settings in the controller or on the unit.
Read the full code guidePower cycle once if you can do that safely. Do not change hidden controller address or header/follower settings.
Read the full code guidePower cycle once if you can do that safely. Do not change group or header/follower settings.
Read the full code guideTurn the system off and power cycle once only if you can do that safely. Do not open the outdoor unit.
Read the full code guideUse the Toshiba Carrier catalog to connect these manual error codes to current model pages and replacement options.
Toshiba Carrier 26 High Wall
Toshiba Carrier 26 High Wall
Toshiba Carrier 26 High Wall
Toshiba Carrier 26 High Wall
Toshiba Carrier 26 High Wall
The Toshiba Carrier troubleshooting table lists E01 as no header remote controller. It points to incorrect remote controller setting, a header remote controller not being set, or no signal being received from the indoor unit.
The Toshiba Carrier table lists E02 as a remote controller transmission error. It says no signal can be sent to the indoor unit and lists system interconnection wires, the indoor PCB, and the remote controller as parts to check.
The Toshiba Carrier table lists E03 as an indoor unit to remote controller regular communication error. It says data is not being received from the remote controller or network adapter.
The Toshiba Carrier table lists E04 as an indoor unit to outdoor unit serial communication error. It points to the system interconnection wires, indoor PCB, and outdoor PCB.
The Toshiba Carrier table lists E08 as duplicated indoor addresses. It says the indoor address setting is wrong because the same address as the unit's own address was detected.
The Toshiba Carrier table lists E09 as duplicated header remote controllers. It says two remote controllers are set as header in double-remote control.
The Toshiba Carrier table lists E10 as CPU-CPU communication error. It points to the indoor PCB and says communication between the main MCU and motor microcomputer MCU is abnormal.
The Toshiba Carrier table lists E18 as header unit to follower unit regular communication error. It says communication is impossible between header and follower indoor units, including twin header/follower units.
The Toshiba Carrier table lists E31 as IPDU communication error. It says communication between the IPDU and CDB is abnormal and points to the outdoor unit.
The Toshiba Carrier table lists F01 as indoor heat exchanger sensor TCJ error. It says an open or short circuit has been detected and lists the TCJ heat exchanger sensor and indoor PCB as parts to check.
The Toshiba Carrier table lists F02 as indoor heat exchanger sensor TC error. It says an open or short circuit has been detected and lists the TC heat exchanger sensor and indoor PCB as parts to check.
The Toshiba Carrier table lists F04 as outdoor discharge temperature sensor TD error. It says an open or short circuit has been detected and lists the outdoor TD temperature sensor and outdoor PCB as parts to check.
The Toshiba Carrier table lists F06 as outdoor temperature sensor TE/TS error. It says an open or short circuit of a heat exchanger temperature sensor has been detected and lists outdoor temperature sensors TE/TS and the outdoor PCB.
The Toshiba Carrier table lists F07 as TL sensor error. It says the TL sensor may be displaced, disconnected, or short-circuited.
The Toshiba Carrier table lists F08 as outdoor outside air temperature sensor error. It says an open or short circuit has been detected and lists the TO outdoor temperature sensor and outdoor PCB as parts to check.
The Toshiba Carrier table lists F10 as indoor room temperature sensor TA error. It says an open or short circuit has been detected and lists the TA room temperature sensor and indoor PCB as parts to check.
The Toshiba Carrier table lists F12 as TS sensor error. It says the TS sensor may be displaced, disconnected, or short-circuited.
The Toshiba Carrier table lists F13 as heat sink sensor error. It says abnormal temperature was detected by the IGBT heat-sink temperature sensor.
The Toshiba Carrier table lists F15 as temperature sensor connection error. It says the TE and TS sensors may be connected incorrectly.
The Toshiba Carrier table lists F29 as indoor unit other PCB error and identifies it as an indoor PCB EEPROM error.
The Toshiba Carrier table lists F31 as outdoor unit PCB error and identifies it as an outdoor PCB EEPROM error.
The Toshiba Carrier table lists H01 as outdoor compressor breakdown. It points to the current-detect circuit and power voltage, including current releasing control at minimum frequency or short-circuit current after direct excitation.
The Toshiba Carrier table lists H02 as outdoor compressor lock. It points to the compressor circuit and says compressor lock was detected.
The Toshiba Carrier table lists H03 as outdoor current detect circuit error. It points to the current-detect circuit and outdoor PCB and describes abnormal current in AC-CT or phase loss.
The Toshiba Carrier table lists H04 as case thermostat operation and describes it as a malfunction of the case thermostat.
The Toshiba Carrier table lists H06 as outdoor low-pressure system error. It points to current, the high-pressure switch circuit, and outdoor PCB, and says a pressure sensor error or low-pressure protective operation was activated.
The Toshiba Carrier table lists L03 as duplicated header indoor units. It says two or more header units are set in the same group.
The Toshiba Carrier table lists L07 as group line in individual indoor unit. It says at least one group-connected indoor unit exists among individual indoor units.
The Toshiba Carrier table lists L08 as indoor group address not set. It says the indoor address group is not set.
The Toshiba Carrier table lists L09 as indoor unit capacity not set. It says the unit capacity has not been set.
The Toshiba Carrier table lists L10 under outdoor unit PCB and identifies it as an outdoor PCB jumper wire, for service, setting error.
The Toshiba Carrier table lists L20 as LAN communication error. It points to address setting, central control remote, and network adapter, and says an address is duplicated in central control communication.
The Toshiba Carrier table lists L29 as other outdoor unit error. It includes communication error between the IPDU MCU and CDB MCU and abnormal temperature detected by the IGBT heat-sink temperature sensor.
The Toshiba Carrier table lists L30 as abnormal external input into indoor unit, interlock. It points to external devices and outdoor PCB, and says there is an abnormal stop due to incorrect external input into CN80.
The Toshiba Carrier table lists L31 as phase sequence error and says abnormal phase sequence of three-phase power was detected. It points to the power supply phase sequence and outdoor PCB.
The Toshiba Carrier table lists P01 as indoor fan error. It points to the indoor fan motor and indoor PCB and says the indoor AC fan error occurs when the fan motor thermal relay is activated.
The Toshiba Carrier table lists P03 as outdoor discharge temperature error and describes it as an error in discharge-temperature releasing control.
The Toshiba Carrier table lists P04 as outdoor high-pressure system error. It points to the high-pressure switch and says IOL activated or high-pressure releasing control using TE is in error.
The Toshiba Carrier table lists P05 as open phase detected. It says the power wire may be connected incorrectly and directs checking open phase and power supply voltages.
The Toshiba Carrier table lists P07 as heat sink overheat. It says abnormal temperature was detected by the IGBT heat-sink temperature sensor.
The Toshiba Carrier table lists P10 as indoor water overflow. It points to the drain pipe, clogged drainage, float switch circuit, and indoor PCB, and says drainage is out of order or the float switch activated.
The Toshiba Carrier table lists P12 as abnormal operation of indoor fan. It points to an abnormal indoor fan motor, indoor PCB, and indoor DC fan conditions such as overcurrent or lock.
The Toshiba Carrier table lists P15 as gas leakage detected. It says there may be gas leakage from a pipe or connecting part and directs checking gas leakage.
The Toshiba Carrier table lists P19 as 4-way valve error. It points to the 4-way valve and indoor temperature sensors TC/TCJ, and says the error is due to temperature drop of the indoor heat exchanger during heating.
The Toshiba Carrier table lists P20 as high-pressure protective operation and identifies it as high-pressure protection.
The Toshiba Carrier table lists P22 as outdoor fan error. It points to the outdoor fan motor and outdoor PCB and says overcurrent or locking was detected in the outdoor fan drive circuit.
The Toshiba Carrier table lists P26 as outdoor inverter Idc activated. It points to IGBT, outdoor PCB, inverter wiring, and compressor, and says short-circuit protection for compressor drive circuit devices was activated.
The Toshiba Carrier table lists P29 as outdoor position error. It points to the outdoor PCB and high-pressure switch, and says a compressor motor position error was detected.
The Toshiba Carrier table lists P31 as other indoor unit error. It says another indoor unit in the group is raising an alarm and points to E03, L07, L03, or L08 alarm locations.