Mitsubishi Electric Aircon Starmex 4 Blinks
Use this Mitsubishi Electric Starmex 4 blinks guide to decide when to stop resetting, what to capture, and what to check before parts are quoted.
What Does Mitsubishi Electric 04 / upper lamp 4x / 04 / operation indicator 4x / TR04 / upper lamp 4x / Upper lamp: 4 blinks / Operation indicator: 4 blinks Mean?
Mitsubishi Electric Starmex 4 blinks is listed as indoor control system in Inverter Split, Multi-Split, Single-Split rows such as FP Series, GP Series. 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 04 / upper lamp 4x / 04 / operation indicator 4x / TR04 / upper lamp 4x / Upper lamp: 4 blinks / Operation indicator: 4 blinks returns
If Starmex 4 blinks returns after one reset, stop repeated restarts and get the matching source row diagnosed.
Reset Starmex 4 blinks once
Capture the Starmex 4 blinks pattern first, then power-cycle once only and note whether the same fault returns.
Send these to us
Starmex 4 blinks blinking light, a short video of the blinking-light sequence, Mitsubishi Electric model stickers, affected rooms, and reset result
Send Us What You're Seeing
Share 04 / upper lamp 4x / 04 / operation indicator 4x / TR04 / upper lamp 4x / Upper lamp: 4 blinks / Operation indicator: 4 blinks, your Mitsubishi Electric model, and what happened before it appeared. We'll read it and respond with the right next step before any work is approved.
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 Starmex 4 blinks, take a short video of the blinking-light sequence. | Confirm which PCB or board input Starmex 4 blinks 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 Starmex 4 blinks. | The affected room, indoor board path, wiring route, or local component should be checked first. |
| Several rooms or the outdoor unit show the same Starmex 4 blinks 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 Inverter Split, Multi-Split, Single-Split rows such as FP Series, GP Series. | 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 Starmex 4 blinks 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.
Read Next
Use these if the quote mentions the parts, checks, or repair path this code points to.
Other Mitsubishi Electric Error Codes
If the code you're seeing isn't 04 / upper lamp 4x / 04 / operation indicator 4x / TR04 / upper lamp 4x / Upper lamp: 4 blinks / Operation indicator: 4 blinks, jump to one of these or browse the full Mitsubishi Electric list.
Ready to Get Started?
Send the Starmex 4 blinks blinking light, a short video of the blinking-light sequence, and Mitsubishi Electric model sticker. Send the model sticker so the matching official row can be checked quickly. We can help check whether this is a status row or an active fault.