Component reference
Tactile Switch Digital Welder Panel Faults
Mode selection, gas check, wire inch and stored-program keys depend on tactile switch scan lines.
Component role
A dead key can be a worn switch, broken scan line, bad connector or panel-board fault. It should not be diagnosed as a main-control-board fault until the panel layer is tested.
Repair evidence table
| Function | Fault symptom | First check |
|---|---|---|
| Gas check | No gas test / gas test stuck | Key, cable, solenoid command and panel scan line. |
| Wire inch | No manual wire feed | Key, feeder command, feed motor path and control cable. |
| Mode selection | Cannot change 2T/4T/TIG/MMA | Key matrix and panel board state. |