1
Trouble Shooting
Section 4
Problem
Possible Cause
Corrective Action
Welder turns on but
does not operate.
Broken ground cable or incomplete
connection.
Make sure all cable connections are in good condition and are tightly secured.
Broken weld tool, weld cable or incomplete
connection.
Make sure all cable connections are in good condition and are tightly secured.
Broken control cable.
Verify continuity on all leads in the control cable (black and white only for
contact weld tools).
Shorted trigger switch (trigger LED always
on).
Verify continuity on the trigger switch. Replace if defective.
Faulty trigger switch (trigger LED doesn’t
light when trigger pulled).
Verify continuity on the trigger switch. Replace if defective.
Faulty control board.
Replace control board.
Weld too hot
regardless of voltage
setting.
Shorted main charge SCR.
Replace charge SCR.
Shorted bank charge SCR.
Replace charge SCR.
Faulty voltage potentiometer
Verify voltage pot wiper has a resistance of 0-500 ohms. Replace if defective.
Faulty control board.
Replace control board.
Green ready LED
doesn’t light.
Faulty control board.
Replace control board.
Disconnected LED
Ensure LED is seated in holder and holder is pressed firmly onto bezel.
Faulty LED
Replace LED
Green ready LED
blinks, welder doesn’t
operate.
Faulty control board.
Replace control board.
Voltage Adjust knob turned up too high.
Turn the Voltage Adjust knob counter-clockwise. Check voltage adjust
potentiometer for correct functionality.
Faulty voltage potentiometer.
Verify voltage pot wiper has a resistance of 0-500 ohms. Replace if defective.
Faulty bank select switch.
Verify switch selects one output per position. Replace if defective.
Yellow contact LED
doesn’t light when
weld tool is placed
against work.
Missing or faulty ground.
Make sure all cable connections are in good condition and are tightly secured.
Broken sense wire (gap weld tool).
Verify continuity on all leads in the control cable.
Disconnect LED.
Ensure LED is seated in holder and holder is pressed firmly onto bezel.
Faulty LED
Replace LED
Faulty control board.
Replace control board.
Red trigger LED
doesn’t light.
Broken control cable.
Verify continuity on all leads in the control cable (black and white only for
contact weld tools).
Control cable not fully connected.
Make sure all cable connections are in good condition and are tightly secured.
Faulty trigger switch.
Verify continuity on the trigger switch. Replace if defective.
Disconnect LED.
Ensure LED is seated in holder and holder is pressed firmly onto bezel.
Faulty LED
Replace LED
Faulty control board.
Replace control board.
Circuit fuse or
CD110 breaker blows
each time unit is
powered on.
Shorted weld capacitor.
Use a capacitance meter to test weld capacitor. Visually inspect weld capacitor
for obvious signs of damage. Replace defective weld capacitor.
Shortened bridge rectifier.
Replace bridge rectifier.
Incorrect primary connections.
Check the jumper links on the transformer.
Shortened transformer.
Replace transformer.
