Table 4-2. Unit Troubleshooting-continued -706880188

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

Table 4-2 Unit Troubleshooting - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

HYDRAULIC SYSTEM - Continued

OUTRIGGERS WILL NOT OPERATE - Continued

Step 4. Check operation of main hydraulic pump.

Use emergency pump to deploy outriggers and refer to Direct Support level to troubleshoot

the main hydraulic pump.

Step 5. Check for malfunctioning of outrigger/aerial interlock (Aerial interlock relay).

See outrigger electrical troubleshooting procedure.

Step 6. Check for malfunctioning of pressure reducer (de-stroking) valve.

Refer to electrical troubleshooting procedure.

Step 7. Check for malfunctioning of diverter valve.

Refer to Direct Support maintenance level to repair or replace diverter valve.

AERIAL CONTROLS WILL NOT OPERATE

Step 1. Check that P. T. O. is engaged.

Engage P. T. O.

Step 2. Check position of manual override.

Ensure manual override is in neutral position and handle moves freely.

Step 3. Check position of diverter valve.

Select AERIAL position with DIVERTER VALVE OUTRIGGER/AERIAL switch.

Step 4. Check that outriggers are extended beyond 18 inches and supporting the weight of the truck.

See para 2-14. for ladder set-up instructions.

Step 5. Check position of RUNILOCK lever.

Engage RUN position with RUNILOCK lever.

Step 6. Check for malfunction of outrigger/aerial interlock (outrigger downlimit switches)

See aerial P. T. O. electrical troubleshooting procedure.

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