T M 1 0 - 4 6 1 0 - 2 3 2 - 12
Table 4-2. Unit Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
Step 3. Check continuity across P11A and P11N.
If the continuity check is okay, notify direct support maintenance.
Step 4. Remove connector P24 from the switch panel. Check continuity across J24A and J24N.
If the continuity check is okay, replace the cable betweenP11 and P24 (para. 4-27).
Media fitter high differential light or horn doesn’t work (Reference Interconnection Diagram FO-1, Sheet 9,
schematic lines 912-913 and Schematic Diagram FO-1, Sheet 10, schematic line 1007).
Refer to light testing and alarm troubleshooting for additional test procedures.
Notify direct support maintenance.
Media filter plugged light is on at a differential less than 20 psid (138 kPa), or is not on at a pressure greater than
30 psid (207 kPa).
Notify direct support maintenance.
Cartrdge filter high differential switch does not work (Reference Schematic Diagram FO-1, Sheet 9, schematic
lines 914-915).
Step 1.
Step 2.
Step 3.
Step 4.
Check operation of switch. Refer to unit PMCS for procedure.
If the switch is not working, go to step 2.
Shut down the ROWPU. Remove connectors P12 and P11 from the control panel, Check for 110-120
VAC across J11A and J12J.
If voltage is not present, notify direct support maintenance.
Check continuity across P11A and P11 H.
If the continuity check is okay, notify direct support maintenance.
Remove connector P24 from the switch panel. Check continuity across J24A and J24H.
If the continuity check is okay, replace the cable between P11 and P24 (para. 4-27),
Cartridge filter high differential light or horn doesn’t work (Reference Schematic Diagram FO-1, Sheet 9,
Shematic lines 915-916 and Schematic Diagram FO-1, Sheet 10, schematic line 1008).
Refer to light testing and alarm troubleshooting for additional test procedures.
Notify direct support maintenance.
Cartridge filter plugged light is on at a differential pressure less than 12 psid (83 kPa), or is not on and differential
pressure is greater than 20 psid (138 kPa).
Notify direct support maintenance.
Feed pressure low switch does not work (Reference Schematic Diagram FO-1, Sheet 9, schematic lines
917-918).
Check operation of switch. Refer to unit PMCS for procedure.
If switch does not work, notify direct support maintenance.
Feed pressure low light or horn does not work (Reference Schematic Diagram FO-1, Sheet 9, schematic line
920, and Schematic Diagram FO-1, sheet 10, schematic line 1009).
Refer to light test and alarm circuit troubleshooting for additional test procedures.
Notify direct support maintenance.
Feed pressure low light is not on and the feed pressure is 3 psig (21 kPa) or less, or, the light is on and the feed
pressure is 10 psig (69 kPa) or higher.
Notify direct support maintenance.
Air compressor switch does not work (Reference Interconnection Diagram FO-1, Sheet 8) (schematic line
824).
Notify direct support maintenance.
Air compressor is on at more than 1850 psig(12755 kPa) or, is not on at less than 1400 psig (9653 kPa).
Notify direct support maintenance.
Change 1 4-45
