E-2
TROUBLESHOOTING
E-2
LN-742 & LN-742H
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
The display is blank. No wire feed
when the gun trigger is activated.
No wire feed when the gun trigger
is activated. The solenoid does not
function. No arc voltage present.
The display board indicates the
LN-742 has input power applied.
1. Make sure the control cable is
connected to the welding power
source correctly.
2. Make sure the welding power
source is turned on and func-
tioning properly.
3. Check the 42 VAC fuse or cir-
cuit breaker in the welding
power source.
1. Check or replace the gun trigger
switch.
2. Check the gun trigger recepta-
cle. Check for loose or faulty
connections.
If all recommended possible areas of
misadjustment have been checked
and the problem persists, Contact
your local Lincoln Authorized
Field Service Facility.