Table 4-2. Unit Troubleshooting-continued -706880255

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

Table 4-2. Unit Troubleshooting - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

ELECTRICAL SYSTEM - PUMP PANEL - Continued

AERIAL LADDER FUNCTIONS WITHOUT OUTRIGGER DEPLOYED

(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 5 and 9 of 16.)

Step 1. Check aerial nested switch for continuity between wires 1230 and 1241 when ladder is nested.

Adjust/replace aerial nested switch (see para 4-9.4).

Step 2. Check outrigger interlock relays for open with all power off between wires 1224 and 1247

(left relay) and 1247 and 1242 (right relay).

Replace interlock relay (see para 4-9.4).

Step 3. With all power off, check front left and front right down relays for open between 1233 and

1249 (left and 1228 and 1248 (right).

Replace down relay (see para 4-9.4).

Step 4. Check outrigger down limit switches for open when outriggers are up.

Adjust/replace outrigger limit switches (see para 4-196).

OUTRIGGER FUNCTION WHILE AERIAL LADDER IS RAISED

(Refer to Electrical Wiring Diagrams, Appendix H, Sheet 5 of 16.)

Step 1. Check aerial nested switch for continuity between wires 1230 and 1241.

Adjust/replace aerial nested switch (see para 4-9.4).

PSI REDUCTION (PUMP DE-STROKE) VALVE DOES NOT ENGAGE WITH DIVERTER SWITCH

IN NEUTRAL POSITION AND AERIAL PANEL T-HANDLE IN "LOCK"

(Refer to Electrical Wiring Diagrams, Appendix H, Sheets 5 and 9 of 16.)

Step 1. Check for +12V at PSI reduction solenoid valve connector.

If 12V is present, repair/replace solenoid valve (see para 4-191).

If 12V is not present, go on to Step 3.

Step 2. Check for +12V at aerial circuit breaker #6.

Replace circuit breaker (see para 4-99).

Step 3. Check for +12V at wire 1304 at RUN/LOCK handle limit switch.

Replace RUN/LOCK limit switch (see para 4-185).

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