Figure 3-12. Control compartment, terminal and control locations
(1) Turn off key switch. Isolate all power circuits
(-) to terminal B2+.
by placing thin cardboard between all pairs of contacts
(8) Measure for 4.5 to 5.5 volts from terminal
on all contractors except the EC contactor.
B2+ (- lead) to terminal I (+ lead).
(2) Remove control compartment cover panel
Note. If the reading of step 18) is
(TM 10-3930-620-12). Connect battery and turn on key
incorrect, test the diode bias block on
the power switch assembly (para 3-9).
(3) Measure for full battery voltage from terminal
(9) Measure voltage between terminal 3 (--)and
8 (-) to terminals B +, B2+, and C2+.
terminal B2+ as follows:
(4) Measure for full battery voltage from terminal
(a) Set directional control switch in forward
2 (-) to terminal B2+.
Note. If incorrect reading is obtained on
(b) With accelerator pedal up, voltmeter
terminals 2, 4. 6. or 7, test resistor
should read below zero.
assembly (para 3-8).
Note. If the reading of step (b) or (c) is
(5) Measure for 0.14 volts from terminal 4 (-) to
incorrect, check the adjustment of the
speed potentiometer (para 3-6 f).
(6) Measure for 13 to 15 volts from terminal 6
(c) With accelerator pedal fully depressed,
to terminal B2+.
voltmeter should read approximately 4 volts.
(7) Measure for 9.5 to 10.5 volts from terminal 7
(d) Voltage reading should vary smoothly