TM 9-4520-260-13
4-22. CONTROL PANEL - CONTINUED
d. Install a known good fuse into the cap and insert into the fuse holder (5). Press in and turn clockwise.
e. Check continuity, as described above, between the two terminals (6 and 7) on the fuse holder. There shall be
continuity. Replace a defective fuse holder.
f. Remove fuse and install cap into fuse holder. As described above, check continuity between the two terminals (6
and 7). There shall be no continuity. Replace a defective fuse holder.
6. THERMOSTAT RECEPTACLE (Typical thermostat and power receptacle shown as item 8 on Figure 4-19).
a. Tag (Item 13, Appendix E) and remove wire from the receptacle to terminal 2 of ECU. Do not allow this wire to
contact other wires leading from the receptacle.
b. Using a multimeter set on the OHMS scale, check for continuity between sockets A, B, and C of the receptacle.
There shall be no continuity. Replace defective receptacle.
7. POWER RECEPTACLE (Typical thermostat and power receptacle shown as item 8 on Figure 4-19).
a. Tag (Item 13, Appendix E) and remove wire from the receptacle to terminal 7 of ECU. Do not allow this wire to
contact other wires leading from the receptacle.
b. Using a multimeter set on the OHMS scale, check for continuity between sockets A, B, and C of the receptacle.
There shall be no continuity. Replace defective receptacle.
8. CAPACITOR ASSEMBLY (9, Figure 4-19).
a. Using a multimeter set on the OHMS scale, place a probe on terminals (10 and 11) of the capacitor assembly.
The small amount of electrical power supplied by the multimeter will induce a slight charge into the capacitor.
b. There shall be some resistance registered on the multimeter. The exact amount of resistance is not important. If
meter reads 0 OHMS, the capacitor assembly is shorted internally and shall be replaced.
c.
Reverse the probes (i.e., probe that was on terminal 11 goes to terminal 12, and probe that was on terminal 12
goes to terminal 11). The resistance indicated on the multimeter shall quickly increase (i.e., pulse higher) and
then return to a lower resistance indication.
NOTE
This pulse of higher resistance indicates the proper discharge of the capacitor assembly
and that the capacitor assembly may be reused. The exact amount of resistance is not
important.
d. If needed, repeat above steps, as required, to verify condition of capacitor assembly.
e. If no pulse in resistance reading can be verified, replace capacitor assembly (9).
CLEANING
Clean components with a dry lint-free cloth (Item 4, Appendix E) or soft-bristle brush (Item 2, Appendix E).
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