TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
NOTE
Circuit breaker 11 is a ground fault breaker. High humidity or moisture around devices
controlled by this breaker may occasionally cause troubles. Check that atmospheric
moisture is not causing the tripping by drying out anything controlled by this breaker.
(9) Check circuit breaker CB11 (REF: Interconnection diagram FO-2, Sheet 8) and
replace if it is faulty (para. 2-23).
AUXILIARY POWER.
Heater power supply, utility outlet, or panel light does not work on auxlliary power. (Ref. Schematic diagram FO-1, sheet 11,
schematic lines 1137-1 138).
Step 1.
Step 2.
Step 3.
Shut down ROWPU and generator. Refer to electrical drawings in Appendix D. Open the control panel door,
plug a powered extension cord into the auxiliary input of the van. Check the operation of relay K27 (REF:
Interconnection diagram FO-2, Sheet 8).
If the relay indicating plunger pulls in, go to step 3.
Disconnect power and disconnect connector P17 (REF: Interconnection diagram FO-2, Sheet 14) from the
control panel. Disconnect the K1 and K2 (REF: Interconnection diagram FO-2, Sheet 6) wires from relay K27.
Check continuity, point-to-point, from J17A (REF: Interconnection diagram FO-2, Sheet 9) to the end of the
K1 wire. Repeat the procedure from J17B to the end of the K2 wire.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace/repair connector J17, if faulty (para. 2-21).
(c) If the continuity checks are good, replace relay K27 (para. 2-23).
Disconnect power and check continuity, point-to-point, from P17A to PB10(2A3) (REF: Interconnection
diagram FO-2, Sheet 12), panel light switch. Repeat the procedure from P17B to CB11(LN) (REF:
Interconnection diagram FO-2, Sheet 8).
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace relay K27 if its contacts, A1 and A3, do not show continuity when the indicating plunger on
K27 is manually depressed when checking continuity (para. 2-23).
(c) If all the above checks indicate the auxiliary power circuit is functioning, refer to heater power supply,
utility outlet, or panel light troubleshooting.
WARNING
Electrical high voltage can cause serious injury or death. Some tests performed in
troubleshooting require power to be connected. Always take proper measures to ensure
personal safety.
NOTE
Ensure that all circuit breakers are set. Refer to electrical drawings in Appendix D.
1. Raw water pump will not start (system normal). (Ref. Schematic diagram FO-1, sheet 6, schematic Iines 619-621).
Control circuits (Ref. Schematic diagram FO-1, sheet 5, schematic Iines 532-537 power circuits).
Step 1. Refer to the operator’s manual and start ROWPU in system “NORMAL”. Observe MS3 (REF: Interconnection
diagram FO-2, Sheet 10) when the raw water pump start switch is pushed. The indicating plunger should go
in and stay in which indicates the control circuits are working properly.
(a) If the indicating plunger goes in and stays in, go to step 10.
(b) If the indicating plunger goes in but comes out when the start button is released, go to step 8.
Change 1
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