Your Toshiba aircon is flashing an error code on the remote controller, or you can tell something’s wrong but no code is displayed. You need to know three things: how to display the code on your specific Toshiba remote, what the code means, and whether you can fix it yourself or need to call a technician.
This guide answers all three. At Lion City Aircon, we’ve serviced over 22,000 aircon units across Singapore since 2016, including thousands of Toshiba splits, cassettes, and SMMS commercial systems. This page is based on official Toshiba service documentation cross-checked against what we actually see in real Singapore homes and offices.
Jump to your section:
- How to Display Your Toshiba Error Code
- Quick Reference Table
- Detailed Error Code Sections
- Repair Cost in Singapore
- Frequently Asked Questions
How to Display Your Toshiba Error Code
Toshiba aircons display the error code on the remote controller during operation. If the display has disappeared, you can use the error log function to recall the most recent fault.
Wired Remote Controller (RBC-AMS series and similar)
When the unit stops due to a malfunction:
- The CHECK indicator on the remote will light up or blink.
- The error code displays alongside the indoor unit number (e.g., “E04 / Unit 1”).
- If the code has cleared from the display, hold the CHECK button (or “Set” + “Test” depending on model) for 5 seconds to recall the malfunction log.
- Use the UP/DOWN buttons to scroll through past error events if multiple are stored.
Wireless Remote (Residential Split Models)
- When the indoor unit detects a fault, the operation LED and timer LED on the indoor unit will flash in a specific pattern.
- Point the remote at the unit and press the CHECK/Test button to enter inspection mode.
- The display will show the error code (e.g., F01, P10, H03).
- Note the code. To return to normal operation, press the CHECK button again or wait 30 seconds.
If You Can’t Get a Code to Display
Common troubleshooting:
- Change the remote batteries. Weak batteries can prevent inspection mode from activating.
- Point the remote directly at the indoor unit sensor (usually behind the front panel, near the LEDs).
- Check the indoor unit’s CHECK LED pattern. Even without a remote display, the LED flash pattern can identify the fault category (slow flash equals communication fault, rapid flash equals sensor or compressor fault).
- If still no response, the indoor PCB or remote receiver may be faulty. Time to call us.
How to Read a Toshiba Error Code
Toshiba codes are made up of a letter and 2 digits. The letter tells you which part of the system is affected:
- E codes: Communication errors (between remote and unit, indoor and outdoor, master and slave)
- F codes: Sensor faults (thermistors on liquid pipe, vapour pipe, discharge, coil, ambient, return air)
- H codes: Compressor and pressure system issues (overcurrent, low pressure detection)
- L codes: Setup and PCB faults (addressing, capacity setting, IPDU)
- P codes: Mechanical and protection faults (fan motor, high pressure, float switch, compressor)
- C codes: TCC-Link central control errors (commercial and group control systems)
If you see two error codes at different times, address the one that appears first on startup. It’s usually the root cause; the second often follows as a downstream effect.
Quick Reference Table: Toshiba Error Codes
| Code | What it Means | Severity |
|---|---|---|
| E01 | No communication between remote controller and indoor unit | Medium |
| E02 | Local controller failure (unable to transmit) | Medium |
| E03 | Master indoor unit receives no data on A-B line | Medium |
| E04 | Indoor unit receives no communication from outdoor unit | High |
| E08 | Duplicated indoor unit address | High |
| E09 | Two local controllers configured as masters in same group | Medium |
| E10 | Indoor unit PSB failure | High |
| E18 | Communications failure between master and slave indoor units | Medium |
| F01 | Indoor unit TCJ (liquid) sensor error | Medium |
| F02 | Indoor unit TC2 (vapour) sensor error | Medium |
| F04 | Outdoor unit TD (discharge) sensor error | Medium |
| F06 | Outdoor unit TE (coil) sensor error | Medium |
| F08 | Outdoor unit TO (ambient) sensor error | Medium |
| F10 | Indoor unit TA (return air) sensor error | Medium |
| F29 | Indoor unit PCB failure | High |
| H01 | Outdoor unit inverter compressor overcurrent | High |
| H02 | Master outdoor unit overcurrent after startup | High |
| H03 | Current detected on master outdoor unit while idle | High |
| H06 | Outdoor unit low pressure detected by Ps sensor | High |
| L03 | Duplicated master indoor units in a group | Medium |
| L07 | Indoor unit in group previously addressed as single unit | Medium |
| L08 | Indoor unit addresses not set | High |
| L09 | Indoor unit capacity not set (DN code 11) | High |
| L29 | Outdoor unit IPDU error (fewer IPDUs detected) | High |
| L30 | Input on indoor PCB CN80 circuit for 1 minute | Medium |
| L31 | Outdoor unit PCB error | High |
| P01 | Indoor unit fan motor error | High |
| P03 | Outdoor unit high discharge temperature (over 115°C) | High |
| P04 | Outdoor unit high pressure switch activated | High |
| P07 | Outdoor unit PCB heat sink overheated (over 90°C) | High |
| P10 | Indoor unit float switch activated | Medium |
| P12 | Indoor unit fan motor error (feedback circuit) | High |
| P19 | Wrong temperature change (4-way valve error) | High |
| P22 | Outdoor unit fan motor IPDU error | High |
| P26 | Outdoor unit giant transistor short circuit | High |
| P29 | Outdoor unit compressor error (feedback circuit) | High |
| P30 | Indoor unit group control follower error or duplicated central control address | Medium |
| P31 | Indoor unit PCB error | High |
| C05 | Central control sending error in TCC-Link device | Medium |
| C06 | Central control receive error in TCC-Link device | Medium |
| C12 | Batch alarm for general purpose equipment interface | Medium |
Communication Errors (E Codes)
E01: No Communication Between Remote Controller and Indoor Unit
The wired or wireless remote isn’t receiving signals back from the indoor unit. Most often we see this from a loose or damaged communication cable (A-B line for wired remotes), failed batteries on wireless remotes, or a defective indoor PCB receiver. Try changing batteries first. If E01 persists, the cable run or PCB needs technician inspection.
E02: Local Controller Failure (Unable to Transmit)
The remote controller itself can’t send signals. Usually means the remote is faulty (water damage, dropped, internal fault). Sometimes the controller PCB has failed. Try a known-working remote first if available. If E02 follows you to multiple units, the remote is bad.
E03: Master Indoor Unit Receives No Data on A-B Line
The master indoor unit in a multi-unit group has lost communication on the A-B control line. We typically find a wire pulled out, a corroded terminal, or a damaged section of cable (in older HDB flats, sometimes hidden behind furniture or in the false ceiling). Visual inspection of the A-B cable run is the first step.
E04: Indoor Unit Receives No Communication From Outdoor Unit
One of the most common Toshiba codes we attend. The indoor unit can’t talk to the outdoor unit. Common causes in Singapore: outdoor unit power isolator switched off, tripped outdoor breaker, damaged transmission cable (U1-U2 line), or a failed PCB on either end. First check we always do: is the outdoor unit isolator switch on? Sounds basic, but you’d be surprised how often a tripped switch is the entire problem.
E08: Duplicated Indoor Unit Address
Two or more indoor units in a system have been set with the same address. This usually happens after a recent reinstallation or addition of new indoor units. Toshiba multi-split systems need each indoor unit to have a unique address. Needs technician to reconfigure DN codes.
E09: Two Local Controllers Configured as Masters in Same Group
For systems using two wired remote controllers (e.g., one in a meeting room, one at reception), only one can be set as “master.” Both being master triggers E09. One controller needs to be reset to “follower” mode. Common after staff have tried to “fix” something themselves with the remote settings.
E10: Indoor Unit PSB Failure
The indoor unit’s power supply board has failed. PSB replacement needed. Expect $250 to $450 depending on model.
E18: Communications Failure Between Master and Slave Indoor Units
For twin or triple indoor unit configurations sharing one outdoor unit. The master and slave indoor units can’t communicate. Check the inter-unit communication cable and connector terminals. Sometimes a slave unit’s PCB has failed.
Sensor Errors (F Codes)
F codes are all thermistor (temperature sensor) related. They share a common fix pattern: identify which sensor is faulty, check the connector contact, replace the thermistor if defective. Most F codes are relatively cheap fixes (parts under $80, full repair from $130).
F01: Indoor Unit TCJ (Liquid) Sensor Error
The thermistor reading liquid refrigerant temperature inside the indoor unit is open or short circuit (resistance measured in kΩ during diagnosis). Common in units over 5 years old. Replacement is straightforward.
F02: Indoor Unit TC2 (Vapour) Sensor Error
Same as F01 but for the vapour-side sensor inside the indoor unit. Same fix pattern.
F04: Outdoor Unit TD (Discharge) Sensor Error
The discharge pipe thermistor on the outdoor unit is faulty. Open or closed circuit at the connector. This sensor monitors compressor discharge temperature, so if it fails the unit may shut down preemptively to protect the compressor. Replacement needed.
F06: Outdoor Unit TE (Coil) Sensor Error
The outdoor coil temperature sensor is faulty. Similar to F04 but on the coil side.
F08: Outdoor Unit TO (Ambient) Sensor Error
The outdoor ambient air temperature sensor is faulty. Less critical for operation (the unit can run on default values) but should be replaced to ensure efficient operation.
F10: Indoor Unit TA (Return Air) Sensor Error
The return air thermistor inside the indoor unit is faulty. This is the sensor reading the temperature of air being pulled into the unit. If it fails, the unit can’t properly modulate cooling.
F29: Indoor Unit PCB Failure
Despite being in the F series, F29 is a board-level fault not a sensor fault. The indoor PCB has failed. Replacement $250 to $450.
Compressor and Pressure Errors (H Codes)
H01: Outdoor Unit Inverter Compressor Overcurrent
The inverter compressor is drawing too much current. Common causes: refrigerant overcharge, compressor lock or seizure, defective inverter PCB. Serious. Don’t keep running the unit. Compressor replacement (if needed) starts from $750.
H02: Master Outdoor Unit Overcurrent After Startup
The compressor draws excessive current shortly after starting. Often a startup capacitor issue, mechanical drag in the compressor, or refrigerant level problem. Diagnosis required.
H03: Current Detected on Master Outdoor Unit While Idle
The system detects compressor current draw when the compressor should be off. Usually a contactor sticking, a defective current sensor, or a PCB control issue. Electrical fault.
H06: Outdoor Unit Low Pressure Detected by Ps Sensor
The low pressure sensor (Ps) detected abnormally low pressure (0.2 bar / -n 2.9 psig). Most often from a refrigerant leak. Other causes: defective Ps sensor, clogged refrigerant piping, stuck expansion valve. Pressure test needed to locate the leak. See our gas top-up guide for more detail.
Setup and PCB Errors (L Codes)
L codes are mostly configuration and addressing errors. They usually appear after installation, after a unit has been added or removed from a system, or after a PCB has been replaced.
L03: Duplicated Master Indoor Units in a Group
Two indoor units in the same group are both set as master. Only one should be. Reconfigure via DN codes.
L07: Indoor Unit in Group Previously Addressed as Single Unit
An indoor unit that was previously running standalone has been incorporated into a group, but its addressing wasn’t updated. Needs DN code reconfiguration.
L08: Indoor Unit Addresses Not Set
One or more indoor units in the system don’t have addresses assigned. Common after fresh installation. The installer needs to complete the addressing procedure before the system can operate.
L09: Indoor Unit Capacity Not Set (DN Code 11)
The indoor unit’s capacity (BTU rating) hasn’t been set on its PCB. DN code 11 needs to be configured to match the actual unit capacity. Usually shows up after a PCB replacement where the technician forgot to set the capacity adapter.
L29: Outdoor Unit IPDU Error (Fewer IPDUs Detected)
The outdoor unit’s Intelligent Power Drive Unit count doesn’t match what’s expected. An IPDU has failed or lost communication. Serious. The compressor and fan control depends on the IPDU. Service required.
L30: Input on Indoor PCB CN80 Circuit for 1 Minute
An external input signal has been held active on the CN80 connector for over 1 minute. Usually means an external accessory (smoke alarm interface, BMS signal, etc.) is sending a continuous signal. Check connected external devices first.
L31: Outdoor Unit PCB Error
The outdoor PCB has failed. Replacement runs $300 to $600 depending on model and capacity.
Mechanical and Protection Errors (P Codes)
P01: Indoor Unit Fan Motor Error
The indoor fan motor isn’t responding. Causes: broken motor windings, harness disconnection, defective indoor PCB. Fan motor replacement runs $200 to $350.
P03: Outdoor Unit High Discharge Temperature (Over 115°C)
The compressor discharge temperature exceeded 115°C. Usually means low refrigerant (the compressor is working harder), restricted refrigerant flow, or a defective discharge thermistor reading false high. Pressure test required.
P04: Outdoor Unit High Pressure Switch Activated
The high pressure protection switch has tripped, detected by high temperature on the TE coil sensor. Most common cause we see in Singapore is a dirty outdoor condenser restricting heat dissipation. Clean the outdoor unit first. Other causes: refrigerant overcharge, defective high pressure switch, clogged piping.
P07: Outdoor Unit PCB Heat Sink Overheated (Over 90°C)
The PCB heat sink temperature exceeded 90°C. Usually from poor ventilation around the outdoor unit (too close to a wall, blocked airflow), failed cooling fan on the PCB, or dust caked on the heat sink. Sometimes resolved by cleaning. Sometimes the fan needs replacement.
P10: Indoor Unit Float Switch Activated
The drain pan’s float switch has detected water buildup. The drain pipe is blocked or the drain pump (in cassette units) has failed. The unit shuts off cooling to prevent water overflow. Common Toshiba issue in Singapore. A proper drain pipe vacuum during servicing usually clears P10 immediately. See our water leak guide for full breakdown.
P12: Indoor Unit Fan Motor Error (Feedback Circuit)
Similar to P01 but specifically detected by the feedback circuit (the motor’s internal sensor reporting back to the PCB). The motor may still spin but isn’t reaching its target speed.
P19: Wrong Temperature Change (4-Way Valve Error)
The 4-way reversing valve (used for switching between cool and heat modes on heat pump models) isn’t operating correctly. Less common in Singapore where cool-only models dominate.
P22: Outdoor Unit Fan Motor IPDU Error
The IPDU controlling the outdoor fan motor has detected a fault. Outdoor fan motor or its drive circuit needs inspection.
P26: Outdoor Unit Giant Transistor Short Circuit
The IGBT (insulated gate bipolar transistor) in the inverter drive has shorted. Serious electrical fault. The inverter PCB usually needs replacement. Cost $300 to $600.
P29: Outdoor Unit Compressor Error (Feedback Circuit)
The compressor isn’t responding correctly according to the feedback circuit. May indicate compressor failure, wiring fault, or IPDU issue. Diagnostic required.
P30: Indoor Unit Group Control Follower Error or Duplicated Central Control Addresses
For systems with TCC-Link central control. Either a follower unit has failed or two units share the same central address. Reconfiguration needed.
P31: Indoor Unit PCB Error
Indoor PCB fault. Same as F29 functionally. Replacement $250 to $450.
Central Control Errors (C Codes)
C codes only appear on systems with TCC-Link central controllers (common in commercial Toshiba SMMS installations, less common in residential).
C05: Central Control Sending Error in TCC-Link Device
The central controller can’t send data to indoor units. Cable or terminal issue.
C06: Central Control Receive Error in TCC-Link Device
The central controller can’t receive data back from indoor units. Same cable or PCB diagnosis pattern as C05.
C12: Batch Alarm for General Purpose Equipment Interface
An external alarm input on the general purpose interface board has been triggered. Check connected external systems first (fire alarm interface, BMS, etc.).
What to Do When You See a Toshiba Error Code
- Note the exact code and any unit number displayed (e.g., E04 / Unit 1).
- Check the severity using the quick reference table above.
- For Medium severity codes: book a service within the next few days. The unit may still work but is degraded.
- For High severity codes: switch the aircon off and call a technician. Running through these risks expensive component damage.
- Try a power reset for communication errors (E codes). Switch off the indoor and outdoor unit isolators for 5 minutes, then restore power. Sometimes resolves transient communication faults.
- WhatsApp +65 8818 5781 with a photo of the error code and your indoor unit nameplate. We can usually identify the likely cause before sending a team.
How Much Does Fixing a Toshiba Error Code Cost in Singapore?
Lion City Aircon pricing across Singapore (HDB, condo, landed, same rate):
- Diagnostic visit: $35 to $50 per unit
- Thermistor replacement (F codes): from $130 (parts and labour)
- Drain pipe vacuum / chemical wash (P10): from $90 per unit
- Capacitor replacement: from $130
- Indoor PCB replacement (E10, F29, P31): $250 to $450
- Outdoor PCB replacement (L31, P26): $300 to $600
- Fan motor replacement (P01, P12): $200 to $350
- Gas leak repair plus recharge (H06, P03): from $180
- Compressor replacement (H01, P29): from $750
- Address or DN code reconfiguration (L codes): usually included in diagnostic visit
If you’re on our annual maintenance contract, diagnostic visits are free and most thermistor and capacitor replacements are included between scheduled visits.
Frequently Asked Questions About Toshiba Error Codes
What’s the most common Toshiba error code in Singapore?
E04 (no communication with outdoor unit) is the most common, followed by P10 (float switch / drain blockage), and P04 (high pressure from dirty outdoor unit). All three are diagnosable in one visit.
Can I clear a Toshiba error code by switching off the aircon?
Communication errors (E codes) sometimes clear with a full power reset, especially if they were caused by a transient power dip. Sensor and mechanical faults (F, H, P codes) won’t clear with a reset because the underlying issue is physical. The code will return.
Why does my Toshiba show two error codes at different times?
Some Toshiba systems display the upstream cause first, then a downstream effect. For example, H06 (low pressure) might be followed by E04 (communication lost) if the unit shuts down hard. Fix the upstream code (the H or P code), and the downstream E code usually clears.
My Toshiba’s CHECK LED is flashing but the remote shows no code. What does that mean?
The LED flash pattern itself indicates a fault category. To read the code, point the remote at the unit and press the CHECK or Test button to enter inspection mode. If still no code displays, the remote receiver on the indoor unit may be faulty.
How do I reset the error log on my Toshiba?
On wired remote controllers, hold the CHECK button for 5 seconds in inspection mode to clear the history. Wireless remotes typically don’t store history; the code shows during operation only.
Should I try to fix Toshiba codes myself?
Filter cleaning, drain pipe checking, basic power resets, and visual inspection of cable connections are safe DIY. Anything involving refrigerant (H06, P03), inverter components (P26, H01), or PCB replacement needs a licensed technician. Refrigerant handling is regulated in Singapore.
Are Toshiba error codes the same across all models?
The core E, F, H, L, P, C code system is consistent across Toshiba residential splits, SkyAir cassettes, and SMMS commercial systems. Some commercial-specific codes appear only on SMMS and SMMSi models. Standard split aircons in Singapore homes use the codes covered above.
Will running my aircon with an error code damage it?
Depends on the severity. Low and medium severity codes won’t cause additional damage if you keep running the unit short-term. High severity codes (H01, P03, P04, P26) can cause catastrophic damage. When in doubt, switch off and ask us.
Get Your Toshiba Aircon Fixed Today
Most Toshiba error codes are diagnosable in a single visit. The longer you wait with an active fault, the more likely cascading damage develops, especially on H and P series codes affecting the compressor.
WhatsApp +65 8818 5781 with a photo of the error code and your outdoor unit’s nameplate. We diagnose remotely where possible and dispatch a team. Same-day service in most cases across Singapore. 22,000+ jobs done since 2016, 5.0★ across 1,500+ Google reviews, BizSafe Level 3 certified.
No scare tactics. No upselling. If your fix is a $130 thermistor, we’ll tell you that and price it accordingly. If it’s a serious inverter or compressor issue, we’ll show you what we found and give you honest repair-versus-replace numbers before doing anything.
WhatsApp Lion City Aircon · Call +65 8818 5781 · Book online
Related reading: Daikin error codes · Aircon not cooling guide · Aircon tripping the breaker · Aircon water leak diagnosis · Toshiba vs Mitsubishi comparison
