TM 5-6350-275-24&P
Table 3-9. Sensors DS Maintenance Troubleshooting - Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
11. FENCE-MOUNTED VIBRATION SENSOR FAILURE (Figure 3-20)
NOTE
Refer to the SAIG for details on the fence-mounted vibration sensor.
Step 1. Remove front cover from processor assembly (1) and make a visual inspection of fuse (9) to see if the
fuse is blown.
If fuse is blown, replace fuse and go to step 3.
If fuse is not blown, go to step 2.
Step 2. Set multimeter to read vac and place multimeter leads across TB1 pins 1 and 2. The multimeter should
read 12 vac.
If multimeter reads 12 vac, go to step 3.
If multimeter does not read 12 vac, replace input power source.
Step 3. Reset alarm by pressing RESET switch (5) up, then releasing.
Step 4. Remove green wire from terminal board (7) pin 6. This should produce a pulsing tone, and alarm relay
should also pulse, indicating line supervision system is working correctly.
If a pulsing tone is produced, line supervision system is working correctly. Reconnect green wire to TB1
pin 6.
If a pulsing tone is not produced, replace the processor PWA (Para. 3-117).
If system is still in alarm, go to step 5.
If system in not in alarm, close and secure processor assembly (1) cover and have workstation operator
verify that system alarm has been cleared.
Step 5. Have someone, starting at far end of sensor line (8), lightly tap each individual sensor (2) with tip of a
screwdriver. The activity light (3) will go on to indicate that sensor is operating. Perform this step until
faulty sensor is located.
Remove and replace faulty sensors (Para. 3-118).
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