TM 10-4610-239-24
TM 08580B-24/3
Table 3-1. Direct Support Troubleshooting - Continued
Malfunction
Test or Inspection
Corrective Action
BACKWASH PUMP ASSEMBLY - Continued
1. PUMP ELECTRIC MOTOR FAILS TO START WHEN BACKWASH SWITCH IS SET TO START -
Continued
If 208 V ac is present on all terminal pairs after repeating step 8, malfunction
caused by faulty heater elements has been corrected.
Step 10.
Shut down ROWPU. Refer to TM 10-4610-239-10. Shut down power. Refer to generator
manual. Refer to schematic diagram FO-3. Check for short circuits between junction box
ground terminal El and motor controller K2 terminals T1, T2, and T3.
If any motor controller terminal is shorted to ground terminal El, go to step 11.
If no motor controller terminal is shorted to ground terminal El, replace motor
controller K2. Refer to paragraph 3-46.
Step 11.
Disconnect backwash pump cable connector P2 from ROWPU. Refer to schematic
diagram figure FO-3. Check for short circuits between P2-D and P2-A, P2-B, and P2-C.
If no pin is shorted to P2-D, go to step 12.
If any pin is shorted to P2-D, go to step 13.
Step 12.
Remove receptacle connector J2 from electrical junction box. Refer to paragraph 3-37.
Refer to schematic diagram figure FO-3. Check for a short circuit between J2-D and motor
controller K2 terminals T1, T2, and T3.
If any terminal is shorted J2-D, repair cable W6. Refer to paragraph 3-17.
If no terminal is shorted to J2-D, replace receptacle: connector J2. Refer to
Step 13.
Remove backwash pump cable assembly. Refer to paragraph 2-138. Refer to schematic
diagram figure FO-3. Check for short circuits between P2-D and P2-A, P2-B, and P2-C.
If any pin is shorted to P2-D, repair backwash pump cable assembly. Refer to
If no pin is shorted to P2-D, repair backwash pump electric motor. Refer to
3-66
