T.O. 33A1-3-358-11/TM 11-6625-842-15
Section IV
NAVAIR 16-30APM239-2
Paragraph 4-29
4-29. LOCALIZATION PROCEDURES. Localizing troubles in the test set is mainly limited to continuity
checking of the test set internal harness and the accessory cables, adaptors and extender boards. However,
certain troubles may develop in the power, control, and meter circuitry of the test set or the fault isolation
meter. A trouble shooting chart is presented in figure 4-3. Schematic diagrams of the test set and the fault
isolation meter are provided in figures 4-4 and 4-5 respectively. Multimeter AN/PSM-6( ) should be used
for fault localization.
WARNING
Use care when working on the 115-volt a-c line connections. Serious
injury or loss of life may result from contact with this voltage.
REMEDY
PROBABLE CAUSE
TROUBLE
1. Check ac power cir-
6 AMP POWER circuit
1. Short circuit in the ac power circuitry,
breaker fails to hold in
cuitry including T1, T2,
ON position.
T3, DS1, and S1 for a
short circuit. Replace
defective components.
2. Defective circuit breaker.
2. Replace circuit
breaker.
3. Short circuit in the 29 volt d-c power
3. Check CR1 through
supply.
CR4, L1, C1, R1, and
R2.
4. Short circuit in meter circuitry.
4. Check S21, M1, and
M2.
Fuse F2 blows after being
Short circuit in the reference regulator, or
Check TB1 and S2 through
replaced.
S13 for short circuit.
the Mode C encoder simulator circuitry.
Replace defective com-
ponents.
Fuse F1 blows after being
Short circuit in the a-c line.
Check S21, CR9, R26,
replaced.
M1, or M2.
6 AMP POWER circuit
1. Defective lamp.
1. Replace lamp.
breaker holds but POWER
ON indicator fails to il-
2. Check the a-c wiring
2. Open circuit in the a-c wiring.
luminate.
up to autotransformer T1
for continuity. Repair or
replace defective wiring.
Proper d-c voltage reading
1. Defective voltmeter.
1. Replace meter.
unattainable.
2. Defective autotransformer.
2. Replace autotrans-
former T2.
3. Defective transformer.
3. Replace T3.
4. Defective diodes.
4. Check CR1 through
CR4.
5. Defective capacitor.
5. Check C1.
Proper a-c voltage reading
1. Defective voltmeter or rectifier.
1. Replace meter or
unattainable.
rectifier.
2. Defective autotransformer.
2. Replace autotrans-
former T1.
Figure 4-3. Trouble Shooting Chart (Sheet 1 of 2)
4-6
Change 4
