Table 4-2. Aviation Unit Maintenance Troubleshooting Procedures (continued)
TEST OR INSPECTION
Step 4. Using a multimeter (Item 13, Appendix B), perform Test 2 (refer to
Figure 4-3 or Figure 4-4 as appropriate) in accordance with the appropriate
charet for your communication system (standard or TEMPEST).
If no failure is detected, the communication cord is working. Replace earphone
or microphone as necessary. Proceed to step 5.
If a failure is detected, and you are using the standard communications
system, unscrew the plug cover and check for any loose connections or cold
solder joints. Resolder any defective connections. Proceed to step 5.
If a failure is detected, and you are using the TEMPEST communications system,
replace the communication cord in accordance with paragraph 4-13f. Proceed
to step 5.
Numbers in test charts correspond to numbered callouts in
TEST 2. Standard Communications System
F R O M T O
1 or 3 7
2 or 4 9
Figure 4-3. Test Points for Standard