◈ GUIDED DIAGNOSTIC COPILOTWork a call one question at a time — evidence board, safety gates, and a senior tech’s discipline. New.READING THE BOARD
TIER 1 · STRAIGHT SHOTOne clear fault. Trace it, find it, fix it.6 meter tests before efficiency points come off
TIER 2 · GOT A TWISTA red herring, or the break is a leg further than it looks.9 meter tests before efficiency points come off
TIER 3 · CALLBACK MAKERMultiple faults, lying symptoms, or a trap that condemns the wrong part.12 meter tests before efficiency points come off
01WHOLE SYSTEM DEAD0/8 CLOSED
Nothing runs. Often traced far upstream.
02OUTDOOR UNIT DEAD0/16 CLOSED
Indoor blower fine, condenser silent.
03RUNS BUT WON’T COOL0/19 CLOSED
Something turns on. Cold never comes.
04NO AIR INSIDE0/6 CLOSED
Condenser runs, registers stay still.
05ACTING POSSESSED0/7 CLOSED
Won’t stop, half-works, or flickers.
06BLOWS FUSES0/5 CLOSED
Something upstream is protecting you.
07GAUGES ON — PRESSURE PROBLEMS0/10 CLOSED
Hook up the manifold. Read the nameplate first.
08WRONG PART, WRONG SIZE0/6 CLOSED
It runs. That does not make it right.