TM-9-2320-273-34

TRUCK TRACTOR, LINE HAUL; LIGHT EQUIPMENT TRANSPORTER; TRUCK CHASSIS; MEDIUM EQUIPMENT TRANSPORTER

TECHNICAL MANUAL; DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE

DECEMBER 1980

TM-9-2320-273-34 - Page 145 of 801

TM 9-2320-273-34

TA 074016

Figure 5-18. Negative Heatsink Test.

c. Diode Trio Test.

Check the diode trio as follows.

(1)

Connect the negative lead of the tester to the output lead of the diode trio and touch the

positive test lead to each of the three copper terminal pads, one at a time, (fig. 5-19). A low resistance

should be indicated, and if a test lamp is used, it should light, If a high resistance reading is obtained, or

if test lamp fails to light, diode trio assembly must be discarded and replaced.

TA 074017

Figure 5-19. Diode Trio Test.

(2)

Connect the positive lead of the tester to the output lead of the diode trio, and touch the

negative test lead to each of the three copper terminal pads, one at a time, as shown above. A high resis-

tance should be indicated, and if a test lamp is being used, it should not light diode trio which does not

pass these tests.

d. Capacitor Test.

The capacitor connected across the heatsink is checked for shorts using an ohm-

meter connected across the terminals (fig. 5-20). A low resistance reading indicates a shorted or leaking

capacitor which must be discarded and replaced.

5-17