Table 4-2. Unit Troubleshooting-continued -706880256

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

Table 4-2. Unit Troubleshooting - Continued

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

ELECTRICAL SYSTEM - PUMP PANEL - Continued

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

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

Step 4. With all power off check for continuity between wires 1304 and 1305 at PSI reduction

manual diverter override relay.

Replace PSI reduction manual diverter override relay (see para 4-9.4).

Step 5. Check for 12V across coil at PSI reduction diverter valve override relay.

If 12V is present, go on to Step 6.

If 12V is not present, go to Step 9.

Step 6. With manual override T-handle in horizontal position, check diverter valve manual override

limit switch for open.

Replace limit switch (see para 4-9.4).

Step 7. With diverter valve switch in neutral position, check for open between wires 1238 and 1270.

Replace switch (see para 4-179).

Step 8. Check for open between wires 12 3 and 1337 on PSI reduction diverter valve relay.

Replace relay (see para 4-9.4).

Step 9. Check wires for continuity.

Replace wire (see para 4-9.4).

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