TM 9-4120-378-14
4.24 CONTROL MODULE. - continued
Location/ltem
Remarks
Action
Inspection
Inspect electrical contacts for corrosion. Replace
e.
or clean as necessary.
- Continued
Temperature
Selector Switch
Test
Tag and disconnect leads.
a.
b.
Check for continuity using a multimeter on the
See fig. FO-2.
lowest ohm setting. Place probes on the red and
blue terminals.
Switch operates in tempera-
Turn switch to COOLER (fully counterclockwise).
c.
ture range of 94F to 56 F
No continuity should exist.
34C to 13 C). If out of
range, immerse bulb in water.
Turn switch to WARMER (fully clockwise). Meter
d.
should show continuity as setting becomes high-
er than bulb temperature.
Place multimeter probes on red and yellow termi-
e.
nals.
f.
Turn switch to WARMER (fully clockwise). No
continuity should exist.
Turn switch to COOLER (counterclockwise). Me-
g.
ter should show continuity as setting becomes
lower than bulb temperature.
Replace if fails above indications.
h.
Evaporator Fan
Speed Switch
Test
a.
Tag and disconnect leads.
See fig. FO-2.
b.
Check for continuity in LOW and HIGH SPEED
position using a multimeter on the lowest ohm
setting.
In LOW SPEED position, there should be conti-
c.
nuity between contacts A2 to A3, and between
B2 to B3. No continuity should exist between A1
to A2 and B1 to B2.
In HIGH SPEED position, there should be conti-
d.
nuity between B1 to B2 and A1 to A2. No conti-
nuity should exist between B2 to B3 and A2 to
A3.
4-47
