01
HVAC
Blower motor failure
confidence
100%
No airflow at the supply registers; motor is hot, surging, or completely dead.
remedyPull the blower door, watch the module for flashing LEDs, then bench-test the motor windings.
SAMPLE RUN · DEMO
This is what the right rail looks like after a diagnostic run.
Nothing was submitted, no photo or audio bytes were queued, and no intake ID was written to the database. The cause list, parts, and procedure below are seeded for a 2nd-year tech rolling up to a no-cool on a communicating furnace throwing an E3 fault — the same shape the live engine returns.
// /demo · sample diagnostic · E3 no-cool
Read the bench tape before you ever upload a photo.
The intake column below is the prefilled symptom — what a tech rolling up to this furnace would tap in on the truck. The right column is what the engine returns: ranked probable causes, a parts cross-reference, and a numbered procedure the tech can run start to finish.
Prefilled intake and ranked probable causes
INTAKE
// pre-loaded · read-onlyWhat the tech wrote up.
The same five inputs the live form collects — locked here so you can read along.
Photo
attached · ir-led-receipt.jpg
Voice note
none
// engine v1 · static scenario · result pre-loaded
RANKED
// top 3 of seedProbable causes, in order.
Each card shows the confidence the engine placed on this fault.
02
HVAC
Low refrigerant charge
confidence
68%
Suction line ices, delta-T collapses at the return, and superheat climbs above design.
remedyRecover the remaining charge, leak-search at the evaporator and line set, then weigh in by spec.
03
HVAC
Bad run/start capacitor
confidence
42%
Outdoor fan hums but does not spin, or hard-starts under load; microfarads drift from nameplate.
remedyDischarge safely, measure MFD against rating (±5%); replace both caps if dual-rated.
Parts cross-reference and repair procedure
PARTS
// 4 stock-or-replace · top-ranked causeCross-reference parts the truck should be carrying.
Anchored to the top-ranked cause’s remedy. The bench updates this list once a real run completes.
| SKU | Part | Source |
|---|---|---|
| MTR-2.0-VAR | ECM blower motor assembly | top-ranked cause · replacement |
| CAP-45/5-DUAL | Dual run capacitor 45/5 µF | match #3 · verify MFD on bench |
| WHL-10X8-CW | Blower wheel 10"×8" CW | top-ranked cause · paired swap |
| R410A-25LB | R-410A refrigerant · 25 lb | match #2 · recover before adding |
// derived from top cause remedy · bench updates post-escalation
PROCEDURE
// ordered · fault-code → fixStep-by-step repair procedure.
Read off the bench tape the same way a tech would walk through it.
- 01
Stage
Read the board
Confirm the E3 cutout on the diagnostic LED sequence and note any co-thrown codes (E4, A5) before touching the refrigerant side.
- 02
Stage
Static pressure check
Pull the blower door and measure both sides of the heat exchanger against spec — a tripping pressure switch often points at a restricted return before it ever points at a refrigerant issue.
- 03
Stage
Leak search
Inspect the evaporator coil and line set with an electronic leak detector. Photograph any pinpoint leak for the warranty file before recovering charge.
- 04
Stage
Weigh in charge
Recover by weight, repair the leak, then weigh in to the nameplate spec — never top off by suction pressure alone. Verify superheat and subcooling at the return before releasing the system.
// Take it for a spin
Run your own diagnostic — or talk to an owner first.
The intake form takes a symptom, an optional fault code, and any attachments you already have on the truck. Or drop a setup brief and an owner reads it before the first call.