Lincoln Electric VANTAGE 400 Service Manual page 96

F-48
FLASHING VOLTAGE TEST (CONTINUED)
TEST PROCEDURE
1. Perform the Case Cover Removal
Procedure.
2. Make sure that the battery is fully charged
and in good condition, and the battery con-
nections are clean and tight.
3. Remove leads 234 and 235 from the oil pres-
sure switch. Insulate or position the lead so it
cannot come in contact with chassis ground
or any other wiring. See Wiring Diagram.
NOTE: Disconnecting leads 234 and 235 bypass
the oil-pressure switch and simulates a running
engine.
4. Place the RUN/STOP switch in the "RUN"
position. (The engine protection light should
remain off.)
5. Connect the voltmeter probes to brush ter-
minals.
6. Measure the voltage; it should read about 3 to
5 VDC.
7. Set the RUN/STOP switch to the "STOP"
position.
8. If the meter reads normal voltage of 3 to 5
VDC, this test is complete.
9. If the meter reading indicates battery voltage,
about 12 to 14 VDC, The rotor may be open,
or the brushes may be faulty or not making
proper contact with the slip rings.
10. Perform the Rotor Resistance Test.
Perform the Brush and Slip Ring Service
Procedure.
11. If the voltage measures zero or very near
zero; this condition could be caused by a poor
connection or a defective component in the
flashing circuit, or a shorted rotor winding.
12. Perform the Rotor Resistance Test.
TROUBLESHOOTING & REPAIR
VANTAGE® 400
11. Refer to the wiring diagram, pull plug P-23
from the control PC board and inspect each
terminal. Make sure that all terminals both on
the board and in the plug are clean and in
good condition, and that the pins are securely
crimped to the flex leads. Perform the follow-
ing additional test.
13. Switch the RUN/STOP switch to the "RUN"
position.
14. Use a voltmeter to check for the presents of
about 12VDC, battery voltage, at the following
locations on the engine protection/ idle control
p.c.b.
(-) Lead #5S (B1) to (+) Lead #232 (J31-1)
(-) Lead #5S (B1) to (+) Lead #232F (J31-2)
(-) Lead #5S (B1) to (+) Lead #200 (J33-5)
NOTE: Lead #232 supplies 12VDC battery volt-
age to the engine protection PC board whenever
the run/stop switch is in the run position.
Lead #200 supplies DC flashing voltage from the
control PC board to the positive slip ring through.
15. If battery voltage is present at all of the
above points; check the top grounding
stud on inside left case from and lead #5H,
also check leads #200, #200B, R3. Make
sure all terminals are crimped tightly to
the flex leads and arc free of corrosion.
F-48