Mitsubishi Electric aircon 10 / LED1 lit, LED2 12x blinking light
Use this Mitsubishi Electric 10 / LED1 lit, LED2 12x blinking light guide to decide when to stop resetting, what to capture, and what to check before parts are quoted.
What does Mitsubishi Electric 10 / LED1 lit, LED2 12x mean?
Mitsubishi Electric 10 / LED1 lit, LED2 12x is listed as zero cross detecting circuit on outdoor power P.C. board in Multi-Split rows such as FP Series, Starmex R32. The loaded row is source-backed by official diagnostic material. Confirm the exact model, series, or signal row before accepting a parts quote.
Indoor or outdoor PCB fault recorded by the source table.
Power supply, connector, fuse, EEPROM, or board-input problem.
Water ingress, surge damage, or wiring issue that must be ruled out before board replacement.
What to do now
Use these steps before another reset or parts quote.
Stop using the unit if 10 / LED1 lit, LED2 12x returns
If 10 / LED1 lit, LED2 12x returns after one reset, stop repeated restarts and get the matching source row diagnosed.
Reset 10 / LED1 lit, LED2 12x once
Capture the 10 / LED1 lit, LED2 12x pattern first, then power-cycle once only and note whether the same fault returns.
Send these to us
10 / LED1 lit, LED2 12x blinking light, a short video of the blinking-light sequence, Mitsubishi Electric model stickers, affected rooms, and reset result
Source-specific guidance
These diagnostic-reference notes help match the code to the exact model. Electrical, refrigerant, wiring, resistance, and component checks are technician work, not DIY steps.
| Source detail | What it says |
|---|---|
| Source repair action | Do not keep resetting the system if this pattern returns. Record the model number, lamp or LED pattern, and affected rooms before booking diagnosis. |
| Singapore / model note | Official Mitsubishi Electric checklist action: Replace outdoor power P.C. board. |
What to check before repair
Use this split to separate safe evidence capture from the tests a technician should prove before quoting parts.
| You can check | Technician should confirm |
|---|---|
| Before resetting 10 / LED1 lit, LED2 12x, take a short video of the blinking-light sequence. | Confirm which PCB or board input 10 / LED1 lit, LED2 12x points to on the source row. |
| Capture the Mitsubishi Electric indoor and outdoor model stickers so the correct family row is used. | Check power supply, fuses, connectors, wiring, and board indicators. |
| Note whether one room, several rooms, or the whole system is affected, plus whether it returns after one reset. | Rule out water ingress, surge damage, and connected component faults before replacing the board. |
What changes the next step
These clues decide whether the first check is room-side, shared outdoor-side, refrigerant-side, source-table, or model-family confirmation.
| What you see | What it points to |
|---|---|
| Only one indoor unit shows 10 / LED1 lit, LED2 12x. | The affected room, indoor board path, wiring route, or local component should be checked first. |
| Several rooms or the outdoor unit show the same 10 / LED1 lit, LED2 12x fault. | The shared outdoor side, power path, communication trunk, or refrigerant circuit needs priority checking. |
| The fault returns immediately after one reset. | Start with the source-row diagnostic branch before approving parts. |
| The model family is different from the row you found online. | Use the model or series filter first; same-looking codes can still belong to different diagnostic tables. |
| The model belongs to Multi-Split rows such as FP Series, Starmex R32. | The loaded row is source-backed by official diagnostic material. Use the matching source row before quoting parts. |
PCB repair or replacement decision
Mitsubishi Electric 10 / LED1 lit, LED2 12x should not jump straight to board replacement. Confirm power, connectors, wiring, and connected parts before deciding whether PCB repair or replacement is justified.
Power, fuse, connector, and water-ingress checks should happen before board replacement.
Connected motors, sensors, or valves can damage or confuse a PCB diagnosis.
Board availability and system age decide whether replacement is sensible.
Mitsubishi Electric 10 / LED1 lit, LED2 12x questions
What does the Mitsubishi Electric 10 / LED1 lit, LED2 12x error mean?
Can I fix a Mitsubishi Electric 10 / LED1 lit, LED2 12x error myself?
Is it safe to keep running the aircon with a 10 / LED1 lit, LED2 12x error?
What causes a Mitsubishi Electric 10 / LED1 lit, LED2 12x error?
Will a Mitsubishi Electric 10 / LED1 lit, LED2 12x error need a repair or a full replacement?
What should I send a technician about a Mitsubishi Electric 10 / LED1 lit, LED2 12x error?
Confirm the fault
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Use these if the quote mentions the parts, checks, or repair path this code points to.