Accessory Isolation Matrix

This matrix is for fast separation of power-source faults from gun, torch, feeder, remote, cooler, cartridge, or mechanized-interface faults.

Use it before disassembling a machine or escalating a board-level diagnosis.

Isolation rules

If one process works and another does not, isolate the failed process path first.
If one accessory package fails and another works, keep the diagnosis on the accessory branch.
Return the machine to a simple baseline before testing advanced modes, memories, pulse packages, or mechanized interfaces.

Accessory isolation matrix

Accessory or subsystem	Symptom that often misleads techs	Fast isolation move	If the complaint follows the accessory	If the complaint stays with the base machine
MIG gun and liner	birds-nesting, erratic feed, weak arc, burnback	remove tip and test bare-wire feed, inspect liner and drive rolls	repair gun path, liner, tip, trigger, or front-end wear	continue into feeder motor, drive control, or output path
Spool gun	aluminum feed instability, soft-wire birdsnest, poor arc blamed on machine	switch back to known-good steel MIG baseline	keep diagnosis on spool gun, soft-wire handling, gas, and setup	inspect base machine only after plain MIG is also abnormal
TIG torch	no start, contaminated tungsten, poor gas coverage	substitute simple known-good torch and baseline DC TIG setup	keep diagnosis on torch, gas hose, front-end parts, valve/cable path	move to remote, gas solenoid, or base output only after torch passes
Foot pedal or hand remote	erratic current control, no start, wrong output response	unplug remote or substitute known-good control and retest in expected mode	repair remote, connector, control mode, or cable	continue into control board or mode logic only after baseline fails
Water cooler and hoses	shutdown, hot torch, poor duty behavior, flow concerns	run approved air-cooled or simplified setup if possible, verify cooler flow and hose routing	keep diagnosis on cooler, hoses, torch package, and interconnects	move to thermal or power-source diagnosis if behavior stays unchanged
Work clamp and return path	no arc transfer, unstable start, weak output	move clamp to bright clean metal close to work, inspect jaws and cable heating	repair clamp, return cable, or grounding strategy	continue into output-current path or control logic
Plasma torch lead	no start, intermittent start, fault after movement	inspect strain points and compare with known-good torch or lead if available	keep diagnosis on torch head, lead, trigger, or connector	continue into air/control only after torch branch is cleared
Plasma cartridge or consumable stack	no pilot, poor cut, repeated readiness fault	replace with known-good correct cartridge or consumable set	stay on cartridge, torch seating, cap, or consumable choice	continue into torch communication or power section after replacement fails
Mechanized/CNC interface	cutting fails only on table or with height control	retest in manual handheld baseline if supported	keep diagnosis on interface wiring, height control, start signal, or CNC logic	continue into cutter only if manual baseline is also faulty
Wire feeder/control cable	no wire output, bad arc, unstable remote feeder behavior	test direct output at studs or with simplified feeder path	stay on feeder, control cable, gun, and compatibility branch	continue into base output only after direct-output baseline fails
Engine-driven feeder or remote package	weak wire process but normal stick or auxiliary power	test direct stick output at machine studs, remove feeder complexity	keep diagnosis on accessory power, control lead, feeder compatibility	continue into engine regulation or output section if direct output is also abnormal

By machine class

Multiprocess machines

First split: basic MIG, stick, and TIG should be tested as separate paths.
If MIG works but TIG does not, stay on torch, gas, remote, and mode selection.
If TIG works but MIG does not, stay on gun, liner, drive rolls, polarity, and feeder settings.

Premium TIG platforms

Strip out pulse, memory jobs, and advanced AC values before testing.
Remote and cooler mismatch can mimic power-source failure.
A good stick or DC TIG baseline is more valuable than chasing one bad aluminum parameter stack.

Plasma systems

Start with clamp, air quality, and consumable/cartridge selection.
On SYNC or smart-torch systems, treat torch recognition as part of the accessory path.
If the machine cuts by hand but not on a table, the table is part of the fault tree.

Engine-driven systems

Separate engine, weld output, auxiliary power, and accessory-fed wire process complaints.
Test at the studs before diagnosing through a feeder.
Remove auxiliary electrical and air loads before interpreting weak-weld complaints.

High-value substitutions

Substitution is most valuable when a known-good item is available:

known-good MIG gun
known-good foot pedal or TIG remote
known-good torch package
known-good work clamp
known-good plasma cartridge or consumable set
known-good feeder control cable

If the symptom follows the substituted item, stop broadening the diagnosis.

Source posture

This matrix is synthesized from repeated troubleshooting patterns across the model guides in this library.
It is intended as a field workflow aid, not as a replacement for model-specific setup procedures or manufacturer instructions.