Trane Mini Split 3-TIME BLINK Error Code
Check your model first
- Trane ML series (Mitsubishi-built NTXWMT/NAXWMT) service manual
Match the model on your equipment label to the linked manufacturer documentation. The same code can mean different things across model families.
Quick answer
3-TIME BLINK on Trane mini splits means indoor fan motor trouble - the control is not getting rotation feedback from the indoor fan while it should be running. Check for blocked air inlets/outlets, power cycle once, and stop; motor and PCB checks are technician work.
Severity: medium · DIY difficulty: easy
Safety
Stop at the breaker power-cycle and any plug-accessible checks (filters, remote settings, visible wiring). The outdoor unit's capacitor holds a lethal charge and the refrigerant circuit is both pressurized and (on R-32 units) flammable — opening panels or servicing the sealed system is licensed-technician work (EPA 608).
What 3-TIME BLINK means
Trane's troubleshooting table lists 3-TIME BLINK as indoor fan motor trouble. The service manual says the fan rotation feedback signal is not emitted during indoor fan operation, so the control stops the fan and blinks the upper OPERATION INDICATOR lamp 3 times with a 2.5-second pause.
Code meaning varies by series
- Trane ML series (Mitsubishi-built NTXWMT/NAXWMT) service manual: Indoor fan motor feedback fault - motor does not rotate or its feedback signal is missing; service flow A directs a controlled motor check at the connector
First checks before service
1. One-time fault event (power disturbance or transient sensor reading) common DIY
Check: Power-cycle at the breaker/disconnect (or unplug for CPAP), restore, and run the system while watching for the code.
Fix: If the code does not return after a full run cycle, the fault was transient — monitor, no repair needed.
2. Fault persists after a clean reset occasional pro only
Check: If the code returns immediately or every session, note the conditions (startup, heating, after rain).
Fix: A persisting code points at the component the manual assigns to this code — that repair is technician territory.
Sources
- Trane error codes (upper lamp blink table) - SplitAtlas, sourced from Trane MyLinkDrive NTXWMT-A111A(B) Service Manual Section 9 — verified 2026-08-29
- Mitsubishi Electric / American Standard NAXSMT-A111AA (Trane ML-series equivalent) Service Manual, 9-4 Troubleshooting Check Table — verified 2026-08-29
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