00
We get the story
What it's doing, when it started, how old the unit is. Half the diagnosis is knowing what changed.
What every common Mitsubishi Electric fault code means, what you can safely check, and when to call a tech. Sydney repairs since 1991.
Mitsubishi Electric Error Codes Explained
Mitsubishi Fault Codes
Reading a Mitsubishi Electric Code
Mitsubishi Electric shows an E, P, U or F code on the controller or via LED flashes. The letter tells you the area, the number narrows it down.
Mitsubishi Electric throwing a code? First, make sure it is Mitsubishi ELECTRIC and not Mitsubishi Heavy Industries. They are separate companies with different codes, and the badge on your outdoor unit tells you which.
Here is how to pull the code on a Mitsubishi Electric split. With the wireless remote, point it at the unit and press the CHECK button twice. The self-diagnosis starts and the code shows on the remote screen. On a wired wall controller (the PAR type) the code shows on the controller display on its own when a fault is active. On units with no display, the OPERATION light on the indoor unit flashes a count. Watch the pattern and write down how many flashes.
The code is a letter and a number. E codes are communication and controller faults, P codes are sensors and protection, U and F codes are the outdoor unit, refrigerant and compressor. Note the exact code before you restart. Some clear with a restart or a filter clean. Others - low gas, a failed sensor, a 4-way valve or a tired compressor - need a licensed tech with gauges. We have repaired Mitsubishi Electric since 1991. Code not listed? Read it to us on (02) 9820 4500.
One rule first: a single code after a storm or power flicker is often nothing - restart at the isolator and see if it returns. A code that comes straight back is a real fault. And if you are on MELCloud WiFi control and the app has dropped out, that is usually your router, not the air con.
0+
Years of Industry Experience
Licensed, Certified & Insured Technicians
Environmentally Responsible & ARCtick Certified
100% Service Satisfaction Guarantee
Flexible & Affordable Financing Options
Wide Range of Systems & Leading Brands
Most Common Codes
The Mitsubishi Electric Codes We See Most
Top four. Fuller list below.
E6 or E7 - communication error
Indoor and outdoor units not talking, usually an interconnect wiring fault rather than a dead board. Safe check: restart at the isolator for 5 minutes. If it returns, the wiring needs testing - $180 to $400.
P1 - room sensor fault
The intake or room temperature sensor is giving bad readings, so the unit cycles oddly and will not hold temperature. Not a DIY fix - the thermistor needs replacing, around $250 to $300 fitted.
U2 - high discharge temp / low gas
The compressor is running too hot, very often from low gas (a leak). Cooling fades. Needs a licensed tech to check pressures, find the leak and regas. Do not keep running it - you risk the compressor.
P5 / P4 - drain fault
The drain pump or drain sensor has tripped, usually a blocked condensate drain backing up water. Safe check: none beyond switching it off to protect the area. A tech clears the drain - $120 to $150.
The Full Mitsubishi Electric Code List
E codes - communication and controller
E0 / E1 / E2 - remote controller. The wall controller or its wiring. The cheap end to diagnose.
E3 / E4 - controller signal. The remote and indoor unit not receiving each other. Usually the controller cable.
E5 - indoor to outdoor. Communication between the units, usually the interconnect wiring. Restart first; if it returns, $180 to $400.
E6 / E7 - indoor and outdoor communication. Same family, wiring or a board. Tested before any part is replaced.
E8 / E9 - communication fault. Signal lost between the units. Wiring or board, diagnosed first.
EA / Eb - wrong connection. Indoor and outdoor mismatched or miswired. The pairing gets checked.
P codes - sensors and protection
P1 - intake (room) sensor. The room temperature sensor, $250 to $300 fitted.
P2 / P9 - pipe sensor. Coil thermistor faults, $250 to $300.
P4 - drain sensor. Often a blocked drain, $120 to $150 to clear.
P5 - drain pump. A blocked drain or failed pump. Clear and test, sometimes a pump replacement.
P6 - freeze or overheat protection. The coil is icing or overheating, usually low gas or airflow. Wash filters first; if it persists, gauges needed.
P8 - pipe temperature. Pipe temp out of range, often low gas. Needs diagnosis.
PA - forced compressor stop. Often a gas leak detected. Leak find and regas.
U and F codes - outdoor, refrigerant and compressor
U2 - high discharge temp. The compressor too hot, commonly low gas. Leak find and regas, $200 to $350 for the top-up.
U3 / U4 - outdoor thermistors. Sensors on the outdoor unit, $250 to $300 fitted.
U5 - heatsink temperature. The inverter heatsink too hot, often a dirty unit or airflow. Cleaned and tested.
U6 - compressor overcurrent. The compressor straining or the power module. Needs proper diagnosis - do not keep running it.
U8 - outdoor fan protection. The outdoor fan circuit. Tested before replacing.
UE - high pressure. Often a dirty or blocked condenser. Clean the outdoor unit first.
UF - compressor locked. Compressor overcurrent with the compressor not turning. Diagnosed before any part goes in.
UH - current fault. A current sensing fault on the outdoor board. Tested first.
UP - compressor overcurrent. The compressor drawing too much and cutting out. Needs diagnosis.
FA and other F codes - outdoor board or power. Outdoor control or power circuit faults. Tested before replacing. Code sets vary across the range, so treat these as a guide.
Common Factors
What's Actually Gone Wrong
Here's what we find when a unit's not cooling, roughly most common first, and what each one costs to sort. If the unit's frozen over or leaking water, that ties in with cooling too. We've got separate pages on ice on the unit and water leaks if that's what you're seeing.
Restart at the isolator
Turn off at the isolator by the outdoor unit, wait five minutes, switch back on. This clears one-off codes from storms and power flickers. If the code returns, it is a real fault.
Check the controller settings first
Before assuming a fault, check the wall controller is on the right mode and temperature and not in a locked or timer state. If it will not heat, also check it is not stuck in a mode lock. Free to check yourself.
Wash filters and clear the outdoor unit
Rinse the indoor filters and make sure the outdoor unit can breathe. This fixes freeze, overheat and high-pressure codes like P6 and UE and is completely safe to do yourself.
What you should NOT do yourself
Do not open the refrigerant circuit, add gas (Mitsubishi R32 needs accurate charging) or pull apart the boards – that is licensed, ARCtick-certified work. And do not keep resetting a unit throwing the same code; you risk the compressor.
When to Call a Technician
Call a tech when the code returns after a restart and a filter and outdoor-unit clean, when it points to gas (U2, P8, UL), the compressor (U6), a sensor (P1, P2, U3) or a board, or any time the unit ices up, drips, will not heat, or trips the breaker. A diagnostic call is $250 plus GST and we quote the fix before we touch anything. We carry common parts so many faults are sorted same visit.
Diagnosis Process
Mitsubishi Electric Repairs, Done Properly
We read the code, test wiring and sensors, put gauges on for anything gas-related (and charge R32 to measured values, never guesswork), then quote before we start. Mitsubishi Electric is premium gear worth repairing properly. Since 1991, 4.8 stars from 280+ reviews. See our full Mitsubishi Electric repairs page or call (02) 9820 4500.
00
Gauges on, pressures read
Refrigerant pressures tell us straight away if it's a gas problem or something else.
00
Electricals and capacitor tested
We check the capacitor, test the fan motors and go over the electricals for anything on the way out.
00
Coils and filters checked
Covers come off so we can see the state of the coils and filters, not guess at them.
00
Fixed quote before we fix
Once we know the fault, we quote the repair before we start. You decide. Most jobs get done same visit.
Real Jobs
Mitsubishi Electric or Heavy Industries?
These are two separate companies with different codes. If your outdoor unit says Mitsubishi Heavy Industries or MHI, this guide does not apply – call us and we will talk you through the MHI codes instead. The badge on the outdoor unit is how you tell. (02) 9820 4500.
Licensed and Local
NSW licence 273312C, ARCtick AU13058, $20M public liability, our own techs not subbies. We repair every brand and install Panasonic, Daikin and Actron. Family run since 1991.
FAQ's
Mitsubishi Electric Error Codes - Common Questions
E6 is a communication error between the indoor and outdoor units, usually an interconnect wiring fault rather than a dead board. Restart at the isolator for five minutes; if it returns, a tech needs to test the wiring, $180 to $400.
P1 is a room or intake temperature sensor fault. The unit gets bad readings and cycles oddly or will not hold temperature. The thermistor needs replacing, around $250 to $300 fitted – not a DIY job.
No – they are separate companies with different parts, procedures and fault codes. Check the badge on your outdoor unit. This guide is for Mitsubishi Electric (MSZ, MFZ, PEFY). For MHI, call us and we will walk you through those codes.
You can clear one-off codes with a restart, fix airflow codes by washing filters and clearing the outdoor unit, and rule out controller mode locks. A code that keeps returning is a real fault for a licensed tech. Never reset repeatedly – it can damage the compressor.
A diagnostic call is $250 plus GST. Common fixes: capacitor $150 to $180, sensor $250 to $300, fan motor $300 to $500, drain clear $120 to $150, gas top-up $200 to $350 once the leak is fixed, board $400 to $700. Quoted before any work.
Jay’s Air repairs all Mitsubishi Electric models – MSZ, MFZ, PEFY and more. Licence 273312C, ARCtick AU13058, lifetime workmanship warranty on installs, 4.8 stars from 280+ reviews, since 1991. (02) 9820 4500.
If the unit’s under about 10 years and it’s a capacitor, a fan motor or gas, repair it every time. If it’s 12 years plus, running old R22 gas, and the compressor or board’s gone, a new system’s usually the smarter spend. We’ll give you the honest call, not the dearest one. If you’re weighing up a new system, our sizing guide tells you what you actually need.
Yeah, the lot. Daikin, Mitsubishi, Panasonic, Fujitsu, Actron, LG and the rest. Ducted and split, homes and businesses. We do split system repairs and ducted repairs right across Sydney.
Jay’s Air. Family run since 1991, our own blokes not subbies, fixed pricing and no surprises. Licensed (NSW 273312C), ARCtick certified (AU13058), 4.8 stars from 280+ reviews. Give us a bell on (02) 9820 4500 and we’ll get it sorted.