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Mitsubishi outdoor LED 9 blinks: inverter check mode

By How House Works EditorialBased on Mitsubishi Electric manualsChecked against sources Updated

Mitsubishi Electric display

LED 9 blinks

“Inverter check mode”

GL, FS, FH, GS06–24, GS30/36 · MUZ-GL Outdoor Service Manual OBH733J, p. 47; MUZ-FS Outdoor Service Manual OBH873B, p. 31; MUZ-FH Outdoor Service Manual OBH684E, p. 35; MUZ-GS Outdoor Service Manual OBH875B, p. 65
Technician

Outdoor board LED, table 10-3, while the outdoor unit operates. Condition: “The connector of compressor is disconnected, inverter check mode starts.” No row of the indoor lamp table 9-4 uses 9 blinks.

What it means

The indoor lamp tables for GL, FS, FH and GS show most codes as a number of blinks followed by a 2.5-second off period, and they have no 9-blink code. They list 2 to 7 blinks, 14 blinks or more, a steady 0.5-second blink, a lit lamp and, on GL and GS30/36, an upper lamp lit with the lower lamp blinking MSZ-GL Indoor Service Manual OBH732D, pp. 27–28; MSZ-FS Indoor Service Manual OBH872A, p. 24; MSZ-FH Indoor Service Manual OBH683E, p. 24; MSZ-GS Indoor Service Manual OBH874A, pp. 38–39.

Nine blinks is in table 10-3 of the outdoor service manuals, for the LED on the outdoor unit’s inverter P.C. board: “Inverter check mode”. The outdoor unit keeps operating, and the mode starts when the compressor connector is disconnected MUZ-GL Outdoor Service Manual OBH733J, p. 47; MUZ-FS Outdoor Service Manual OBH873B, p. 31; MUZ-FH Outdoor Service Manual OBH684E, p. 35; MUZ-GS Outdoor Service Manual OBH875B, p. 65. That LED stays lit in normal operation; the count is the number of blinks after each 2.5-second pause MUZ-GL Outdoor Service Manual OBH733J, p. 47.

Nine also shows up in two other tables:

  • In failure mode recall, which a technician starts from the remote, 9 blinks of the indoor lamp points to the outdoor unit’s non-volatile memory data or its power module, an IGBT module on MUZ/MUY-GL24 MUZ-GL Outdoor Service Manual OBH733J, p. 44. The manual notes that recall patterns differ from the check table.
  • On P-Series PKA-A and PLA-A units, 9 beeps and blinks in self-check mean E4 or E5, a remote controller signal receiving error. When the lamp first stays on for about 3 seconds (output pattern B), 9 means U6 PKA-A24/30/36KA8 Service Manual TCH115A, p. 12.

Check these first

The LED is on a circuit board in the outdoor unit. The owner’s manuals say the user should not disassemble, alter or repair the unit MSZ-GL Operating Instructions, p. En-1, so this count is read by a technician.

  1. Stop the unit with the remote and consult your dealer. The owner’s manuals list a blinking operation indicator lamp as a reason to stop using it MSZ-GL Operating Instructions, p. En-11; MSZ-FS Operating Instructions, p. En-13.
  2. Do not switch the breaker off and on while the unit runs; the owner’s manuals warn of sparks and fire. Switch the unit off with the remote before turning the breaker off MSZ-GL Operating Instructions, p. En-1.

Inverter check mode itself is listed with the outdoor unit running. The table does not say what the indoor lamp shows at the same time.

When to call a licensed technician

  • The table’s remedy: check that the compressor connector is connected correctly, then follow “How to check inverter/compressor” in section 10-5 MUZ-GL Outdoor Service Manual OBH733J, p. 47.
  • The service manuals say to turn the power off before removing the panels and the electronic control P.C. board, to discharge the capacitor before work on electric parts, and to keep clear of live parts when a circuit has to be checked with power on MUZ-GL Outdoor Service Manual OBH733J, pp. 2, 41.

Notes for different models

  • The inverter check mode row reads the same in all four outdoor manuals cited above.
  • In recall mode, the power module row names IC700 as a power module on MUZ/MUY-GL09/12/15/18 and as an IGBT module on MUZ/MUY-GL24 MUZ-GL Outdoor Service Manual OBH733J, p. 44. The FH table lists FH09/12 and FH15/18 for this part, while its condition text names FH06/09/12 MUZ-FH Outdoor Service Manual OBH684E, p. 32.

Related Mitsubishi Electric codes

See also

Other ductless mini-splits: Daikin, Fujitsu, MrCool

All Mitsubishi Electric codes

Mitsubishi Electric is a trademark of its owner. How House Works is not affiliated with or endorsed by Mitsubishi Electric.

Sources

  1. Mitsubishi Electric Corporation. MSZ-GL Indoor Service Manual OBH732D. No. OBH732, Revised Edition-D, issued Feb. 2022; covers MSZ-GL06–24NA and MSY-GL09–24NA. Accessed Oct 12, 2026.
  2. Mitsubishi Electric Corporation. MUZ-GL Outdoor Service Manual OBH733J. No. OBH733, Revised Edition-J, issued Jun. 2021; covers MUZ-GL09–24NA and NAH, MUY-GL09–24NA (the cover lists no MUZ-GL06). Copy hosted by a Mitsubishi distributor (Gemaire/Baker Distributing).. Accessed Oct 12, 2026.
  3. Mitsubishi Electric Corporation. MSZ-FS Indoor Service Manual OBH872A. No. OBH872, Revised Edition-A, issued Nov. 2021. Accessed Oct 12, 2026.
  4. Mitsubishi Electric Corporation. MUZ-FS Outdoor Service Manual OBH873B. No. OBH873, Revised Edition-B, issued Aug. 2021; covers MUZ-FS06–18NA and NAH. Accessed Oct 12, 2026.
  5. Mitsubishi Electric Corporation. MSZ-FH Indoor Service Manual OBH683E. No. OBH683, Revised Edition-E, issued Nov. 2021. Copy hosted by a Mitsubishi distributor (Gemaire).. Accessed Oct 12, 2026.
  6. Mitsubishi Electric Corporation. MUZ-FH Outdoor Service Manual OBH684E. No. OBH684, Revised Edition-E, issued Jun. 2021; covers MUZ-FH06–18NA and NAH. Copy hosted by a Mitsubishi distributor (Gemaire).. Accessed Oct 12, 2026.
  7. Mitsubishi Electric Corporation. MSZ-GS Indoor Service Manual OBH874A. No. OBH874, Revised Edition-A, issued Oct. 2022; covers MSZ-GS06–36 and MSY-GS09–36; table 9-4 is on p. 38 for GS06–24 and p. 39 for GS30/36. Copy hosted by a Mitsubishi distributor (Meier Supply).. Accessed Oct 12, 2026.
  8. Mitsubishi Electric Corporation. MUZ-GS Outdoor Service Manual OBH875B. No. OBH875, Revised Edition-B, issued Oct. 2022; covers MUZ-GS NA, NAH and NAHZ, MUY-GS NA, and the GS30/36 NA2 and NAH2 outdoor units. Copy hosted by a Mitsubishi distributor (Meier Supply).. Accessed Oct 12, 2026.
  9. Mitsubishi Electric. MSZ-GL Operating Instructions. Printed code DG79A01LH01 (the file name says JG79Y190H02); no publication date printed; covers MSZ-GL06/09/12/15NA and MSY-GL09/12/15NA; English pages are numbered En-1 onward. Accessed Oct 12, 2026.
  10. Mitsubishi Electric. MSZ-FS Operating Instructions. Printed code JG79Y766H01; no publication date printed; covers MSZ-FS06/09/12/15/18NA; English pages are numbered En-1 onward. Accessed Oct 12, 2026.
  11. Mitsubishi Electric Corporation. PKA-A24/30/36KA8 Service Manual TCH115A. No. TCH115, Revised Edition-A, August 2023. Accessed Oct 12, 2026.