Tweco SC10 - Manual (Page 36)

CUSTOMER/OPERATOR SERVICE 5-6 Manual 0-2479
H. Motor/Tachometer Tests
Move torch up and down manually in both high and
low speed. If lifter operates at high speed in both
cases either the motor tachometer or connections from
it may be open. Measure voltage between J10-4 and
J10-5. If voltage is approximately 10 to 15 vdc either
plus or minus the motor is okay, replace the Standoff
Control Assembly. If near zero, repeat the measure-
ment at the motor.
The motor has two sets of brushes, the set to the rear
is for the tachometer. If this also is near zero with the
motor moving replace the motor/tachometer. Oth-
erwise check for faulty connections between the mo-
tor and J10 (lifter assembly connector, motor cable,
J43 to J10 harness).