Wired Remote Signal Test (Y1/Y2/Y3)
Quick Answer
Y1 to Y3: 12 V DC, must be ≥ 11.4 V DC
Pulse signal: 7–12 V DC (pulsing)
What is it?
A check of remote controller supply and signal integrity on systems using Y1/Y2/Y3 terminals.

Tools
Digital Multi Meter (DC voltage)
Procedure
Measure Y1 to Y3.
Remove Y2 conductor.
Measure:
Y3 to the disconnected Y2 cable (to indoor)
Y3 to the Y2 terminal



Pass Criteria
Y1–Y3 ≥ 11.4 V DC
Pulse signal present in the 7–12 V DC range.
If it fails (Solution)
Y1–Y3 < 11.4 V DC or 0 V:
Action: Check wiring continuity; if wiring is OK, replace controller PCB / address supply issue.No pulse signal:
Action: Repair wiring between remote and indoor; then re-run “System Signal Test (Indoor ↔ Outdoor)”.