Table 4-2. Unit Troubleshooting-continued -706880263

TM 5-4210-233-14&P-1

4-2. Unit Troubleshooting-Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

ELECTRICAL SYSTEM - AERIAL CONTROL PANEL - Continued

AERIAL DISCHARGE VALVE DOES NOT CLOSE WITH PANEL SWITCH - Continued

Step 4. Check wiring for continuity.

Replace wire (see para 4-9.4).

Step 5. Refer to "+12 volts not present at aerial master buss" troubleshooting procedure."

Step 6. Refer to "turntable swivel assembly slip ring contact interrupted" troubleshooting procedure.

AUDIO ALARM DOES NOT FUNCTION

(Refer to Electrical Wiring Diagrams, Appendix H, Sheets 11 and 12 of 16.)

Step 1. Check switch for proper operation.

Replace switch (see para 4-9.4).

Step 2. Check alarm sounds when 12V is applied across terminals.

Replace alarm (see para 4-9.4).

Step 3. Check aerial circuit breaker#4 for +12V.

Replace circuit breaker (see para 4-99).

Step 4. Check wiring for continuity.

Replace wire (see para 4-9.4).

Step 5. Refer to "swivel assembly slip ring contact interrupted" troubleshooting procedure.

Step 6. Refer to "aerial circuit +12 volts not present at aerial master buss" troubleshooting procedure.

LADDER INTERCOM DOES NOT FUNCTION PROPERLY

(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 11 of 16.)

Step 1 Check for +12V at circuit breaker #6 with aerial master circuit on.

Replace breaker (see para 4-99).

Step 2. Check for +12V at aerial panel intercom unit on wire #1237.

Replace wire from breaker (see para 4-9.4).

4-134