Lincoln LT-7, Troubleshooting Manual

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TROUBLESHOOTING AND REPAIR
Observe Safety Guidelines
detailed in the beginning of this manual.
Troubleshooting Guide –
See Wiring Diagrams for location of specified
components. See Wiring Diagrams for troubleshooting of specific circuits.
B-3 B-3
LT-7 TRACTOR
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact the Lincoln
Electric Service Department for electrical technical troubleshooting assistance before you proceed.Call 216-383-2531 or 1-800-
833-9353
CAUTION
FUNCTIONAL PROBLEMS
PROBLEMS
(SYMPTOMS) FIELD
COURSE OF ACTION RECOMMENDED SHOP
COURSE OF ACTION
Wire feeds whenever “Power
Switch” (S1) is turned “ON”. 1. Check the “Start Switch”(S5).
Make certain it is not stuck
closed.
2. Check the “Inch Down Switch”
(S4). Make certain it is not
stuck closed.
3. Check the “Inch Up Switch”
(S3). Make certain it is not
stuck closed.
1. If light 1B on the control board
is NOT on, then the control
board may be faulty. Replace.
2. If lights 1B and 1A are both
“ON” then remove lead #593
from the Inch Up switch(S3). If
the problem is resolved the lead
or the switch is faulty. If light 1A
stays on when lead #593 is
removed from the Inch Up switch
the control board may be faulty.
Replace.
3. If lights 1B, on the control
board, and 2B on the logic
board, are both “ON” then
remove lead #581 from the Start
switch(S5). If the problem is
resolved the lead or the switch is
faulty. If light 2B stays on when
lead #581 is removed from the
Start Switch the logic board may
be faulty. Replace.
4. If lights 1B, on the control
board, and 2J on the logic board
are both “ON” then remove lead
#592 from the Inch Down switch
(S4). If the problem is resolved
the lead or the switch is faulty. If
light 2J stays on when lead #592
is removed from the Inch Down
switch the logic board may be
faulty. Replace.