Table 4-2. Unit Troubleshooting-continued -706880265

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

4-2. Unit Troubleshooting-Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

ELECTRICAL SYSTEM - AERIAL CONTROL PANEL - Continued

14 AERIAL LADDER HOIST CYLINDER LOCKING VALVES DO NOT RELEASE LADDER WHEN

RAISE/LOWER CONTROL IS PLACED IN "LOWER" POSITION - Continued

Step 4. Refer to "swivel assembly slip ring contact interrupted" troubleshooting procedure.

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

Step 6. Check wiring for continuity.

Replace wire (see para 4-9.4).

15 ELEVATION SLOW-DOWN VALVE DOES NOT ENGAGE WHEN LADDER REACHES

700 ELEVATION (Refer to Electrical Wiring Diagrams, Appendix H, Sheet 1 0 of 16).

Step 1. Check slow-down valve limit switch for proper operation.

Adjust/replace slow-down valve limit switch (see para 4-197).

Step 2. Check solenoid valve for proper operation by applying 12V to coil.

Repair/Replace valve (see para 4-9.4).

Step 3. Check aerial circuit breaker #5 for +12V.

Replace 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 "+12 volts not present at aerial master buss" troubleshooting procedure.

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