WeldKing Fault-Branch Matrix

This matrix groups recurring WeldKing failures by subsystem so technicians can start from the complaint branch, not just the model name.

How to Use This Matrix

Start here when the symptom is known but the correct subsystem is not.
Open the listed model guides first because they carry the strongest local notes for that branch.
Use the listed local references after the guide has narrowed the branch.

Branch Matrix

Subsystem branch	Recurring symptoms	Strongest models to open first	Best local references	Prove before escalation
Support power, capacitor board, and auxiliary supply	low OCV, fan slowdown, arc dies after short run, clicking or cycling startup, intermittent support collapse	CoolArc160, CoolCut30, MigSonic145, MigSonic200 CVCC	`COOLARC160_Test_instruction.pdf`, `CoolCut30_service_manual.pdf`, `MigSonic145_service_manual.pdf`, `MigSonic200cvcc_service_manual.pdf`	branch power, clamp path, and actual support-voltage behavior under load
Input-sense, VRD, and mode-state branch	wrong 110 V or 220 V recognition, low OCV that may be normal state behavior, hidden reset or debug traps, panel state drift	CoolArc200, PulseWave200, MultiSonic220	CoolArc200 local wiring references, `B.067RM.183-D.pdf`, workbook sheets for `PulseWave200` and `MultiSonic220`	actual input class, VRD expectation, 2T or 4T state, and clean power-cycle reset
Display, ribbon, and control branch	all lights flashing, frozen or crazy digital display, PRO10 or mode confusion, retained bad state after repair	MultiSonic220, PulseWave200, MigSonic252S+SS20	`B.067RM.183-D.pdf`, `B.067RM.205-H.pdf`, `MultiSonic220_owner_manual.pdf`, `MigSonic252S_owner_manual.pdf`	simple baseline process, connector seating, and process reset path
Wire-feed, trigger, and feeder branch	no wire feed, full-speed motor, trigger dead, spool-gun complaints, feeder strange but power source partly healthy	MAG255, MAG251, MAG211, MigSonic145, MigSonic252S+SS20, MultiSonic220	`Mag255_disable_craterfill.pdf`, `mag251manualweb.pdf`, `mag211manual.pdf`, `MigSonic145_service_manual.pdf`, `B.067RM.205-H.pdf`, `MigSonic252S_owner_manual.pdf`	bare-wire feed with tip removed, trigger continuity, correct roller family, chart-correct setup, and spool-gun connection
MAG211 chart, solenoid, and accessory branch	chart-sensitive rough arc, no gas on trigger, one-gun-only failure, or unstable feed with otherwise healthy power	MAG211	`mag211manual.pdf`, workbook sheet `MAG211`	plain-steel MIG baseline, chart-correct setup, solenoid actuation, and base-gun versus spool-gun proving
MAG251 ripple and post-service direction branch	high ripple, rough arc that stays with the machine, or wrong feed direction after board work	MAG251	`mag251manualweb.pdf`, workbook sheet `MAG251`	plain-steel MIG baseline, output-ripple check, and post-service feed-direction proof
MAG255 crater-fill, discharge, and accessory branch	post-trigger wire creep, sparks at the wire tip without trigger, spool-gun-only welding failure, or intermittent feed surge after a healthy baseline	MAG255	`Mag255_disable_craterfill.pdf`, `mag255manual.pdf`, workbook sheet `MAG255`	plain-steel MIG baseline, crater-fill isolation, spool-gun voltage at pins `1` and `9`, and discharge-path proof
MigSonic145 support-power, trigger-wire, and generation branch	compact MIG clicks on and off, low output stays with the machine, trigger stays dead after support-power trouble, or feed goes abnormal after capacitor work	MigSonic145	`MigSonic145_service_manual.pdf`, `MS145_MIN_OUTPUT.doc`, workbook sheet `MigSonic145`	stable `24 V` support first, then correct gun generation, trigger wire, and bare-wire feed
MigSonic252S+SS20 source-side, feeder-package, and spool-gun branch	source readouts freeze, gas stays open, spool gun feeds full speed, or the remote feeder is blamed while the source already looks wrong	MigSonic252S+SS20	`MigSonic252S_owner_manual.pdf`, workbook sheet `MigSonic252S`	power-source baseline first, then feeder package, spool-gun connection, and remote harness branch
Current-path, polarity, and accessory branch	stick or TIG works but MIG is dead, hard start, weak arc, hot leads, wrong process behavior after accessory changes	MultiSonic220, CoolArc160, CoolArc200, MAG255	`MultiSonic220_owner_manual.pdf`, workbook sheets `CoolArc160`, `CoolArc200`, and `MAG255`	polarity connector, Dinse seating, clamp bite, and fitted accessory package
TIG start, HF, remote, and gas-path branch	no HF, tungsten sticking, AC works but DC or start behavior is wrong, remote or pedal confusion, low-current TIG instability	CoolTIG220, PulseWave200, TIG200PACDC	CoolTIG220 service notes, `220V_VERSION_NO_HF.docx`, `Pulsewave200_owner_manual_web.pdf`, `TIG200PACDCmanualsimple version.pdf`	torch polarity, gas flow, torch switch or remote path, HF-versus-no-HF version proof, and simple DC TIG baseline before AC or pulse diagnostics
TIG200PACDC DC-baseline, AC-mode, and `4K7` remote branch	DC TIG works but AC is unstable, only one pedal branch misbehaves, or panel expectations drift only in the remote path	TIG200PACDC	`TIG200PACDCmanualsimple version.pdf`, workbook sheet `TIG200PACDC`	simple DC TIG baseline first, then the AC-only branch and correct `4K7` remote value
Plasma HF, air path, and torch-front-end branch	no HF, postflow with no start, pilot but no transfer, weak cut, torch rebound or blocked gas path, built-in versus external air confusion	ThunderCut65, CoolCut40air, CUT65, CUT40, CoolCut30	`pilot_arc_maitain_current.pdf`, `ThunderCut65_service_manual.pdf`, `W.496RM.418-C.pdf`, `W.496RM.410-C.pdf`, `W.496RM.419-C.pdf`, `CUT65 no HF START.txt`	air under flow, a fresh front end matched to the fitted SG55 or CB50 torch, a clean clamp path, correct torch package, internal-versus-external air mode, and pressure-window proof before board work
Plasma pressure, guide, and torch-mechanics branch	normal postflow but no start, delayed restrike, start improves with pressure changes, tracking faults, or torch-head rebound	ThunderCut65, CoolCut40air, CUT65	`pilot_arc_maitain_current.pdf`, `ThunderCut65_service_manual.pdf`, workbook sheet `CoolCut40air`, and the official A81 or SG55 parts paths	pressure-window or `RV1` response, torch-head return, guide carriage, stand-off, and matched torch hardware
CUT40 external-air, hose-valve, and CB50 branch	external-air no-start, bad hose or valve routing, poor transfer with a healthy clamp, or guide-hardware trouble on the CB50 platform	CUT40	`Cut40_owner_manual.pdf`, workbook sheet `coolcut40air`	dry external air under flow, fresh CB50 front end, clamp path, freehand cut proof, and only then guide hardware before board blame
CUT65 pressure-window, `RV1`, torch-head, and A81 branch	pressure-sensitive pilot, postflow with no start, or A81 stand-off or circle-kit instability on the 65 A family	CUT65, ThunderCut65	`CUT65 no HF START.txt`, `Cut65manual.pdf`, `pilot_arc_maitain_current.pdf`, workbook sheet `ThunderCut65`	pressure-window proof, `RV1` response, torch-head rebound, freehand cut proof, and only then A81 hardware before board blame
Parts, wear-item, and calibration-sensitive branch	repeated false faults after parts replacement, unstable TIG after service, wrong assembly order, package mismatch	CoolTIG220, MultiSonic220, CoolCut40air	CoolTIG220 parts files, CoolTIG220 calibration workbook, `B.067RM.214-A.pdf`, `B.067RM.215.pdf`, `B.067RM.221-A.pdf`	exact fitted package, wear-item stack order, and whether the complaint started immediately after service

Fast Starting Points

If the complaint sounds like...	Start here
low OCV with fan or support-voltage oddities	support power, capacitor board, and auxiliary supply
wrong voltage display or low OCV that may be normal	input-sense, VRD, and mode-state branch
MIG dead while stick or TIG still works	current-path, polarity, and accessory branch
feeder runs away, no feed, or spool-gun acts wrong	wire-feed, trigger, and feeder branch
chart-sensitive rough arc, no gas on trigger, or one-gun-only failure	MAG211 chart, solenoid, and accessory branch
rough arc with ripple feel or wrong feed direction after board work	MAG251 ripple and post-service direction branch
wire creep after stop, sparks at the tip without trigger, or spool-gun-only no-weld	MAG255 crater-fill, discharge, and accessory branch
compact MIG clicks on and off or loses trigger after support-power trouble	MigSonic145 support-power, trigger-wire, and generation branch
source readouts freeze or the remote feeder is blamed while the source already looks wrong	MigSonic252S+SS20 source-side, feeder-package, and spool-gun branch
no HF or unstable TIG start	TIG start, HF, remote, and gas-path branch
DC TIG is healthy but AC is unstable, or only one pedal branch misbehaves	TIG200PACDC DC-baseline, AC-mode, and `4K7` remote branch
air flows but plasma will not really start or cut	plasma HF, air path, and torch-front-end branch
postflow is normal but start or tracking is still wrong	plasma pressure, guide, and torch-mechanics branch
external-air no-start or CB50 guide trouble on the 40 A family	CUT40 external-air, hose-valve, and CB50 branch
pressure-sensitive pilot or A81 hardware instability on the 65 A family	CUT65 pressure-window, `RV1`, torch-head, and A81 branch

Notes

WeldKing has enough local service material that branch-first diagnosis is usually faster than category-first diagnosis.
The strongest branch evidence lives in CoolArc160, CoolArc200, MAG211, MAG251, MAG255, MultiSonic220, CoolTIG220, PulseWave200, CoolCut40air, and ThunderCut65.
The wider WeldKing intake layer now carries direct evidence branches for MigSonic145, MigSonic252S+SS20, TIG200PACDC, CUT40, and CUT65 too, so those families no longer have to hide behind generic MIG, TIG, or plasma buckets.