TM 5-2420-231-23-1
0031
Table 1. Heating, Ventilation, and A/C (HVAC) Blower Motor Does Not
Operate at One or More Speeds - Continued.
031
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
6. Using a digital multimeter, mea-
HVAC Blower Motor Does
Resistance 5.0 Ohms or Less -
sure resistance between cab wir-
Not Operate at One or More
Replace HVAC blower motor (WP
ing harness connector (WP 0007,
Speeds - Continued
0349).
Figure 129) terminal A3 and cab
Install blower fan switch (WP 0172).
wiring harness connector (WP
Connect all wiring harness connectors.
0007, Figure 148) terminal C.
Proceed to Test Step 14.
Resistance should be 5.0 ohms or
Resistance Greater Than 5.0 Ohms -
less.
Replace cab wiring harness (WP 0181).
Install blower fan switch (WP 0172).
Proceed to Test Step 14.
Test Step 4. Test HVAC Blower Motor
Medium-Speed Circuit.
1. Disconnect side console wiring
harness connector (WP 0007, Fig-
ure 130) from cab wiring harness
connector (WP 0007, Figure 129).
2. Using a digital multimeter, mea-
Resistance 5.0 Ohms or Less -
sure resistance between side con-
Proceed to step 3.
sole wiring harness connector (WP
Resistance Greater Than 5.0 Ohms -
0007, Figure 145) medium speed
Replace side console wiring harness
terminal and side console wiring
(WP 0170).
harness connector (WP 0007, Fig-
Install blower fan switch (WP 0172).
ure 130) terminal A4. Resistance
Proceed to Test Step 14.
should be 5.0 ohms or less.
3. Remove headliner and right-side
cover (WP 0346).
4. Remove right blower duct (WP
0350).
5. Disconnect cab wiring harness
connector (WP 0007, Figure 148)
from blower motor wiring harness
connector (WP 0007, Figure 149)
(WP 0349).
6. Using a digital multimeter, mea-
Resistance 5.0 Ohms or Less -
sure resistance between cab wir-
Replace HVAC blower motor (WP
ing harness connector (WP 0007,
0349).
Figure 129) terminal A4 and cab
Install blower fan switch (WP 0172).
wiring harness connector (WP
Connect all wiring harness connectors.
0007, Figure 148) terminal B.
Proceed to Test Step 14.
Resistance should be 5.0 ohms or
Resistance Greater Than 5.0 Ohms -
less.
Replace cab wiring harness (WP 0181).
Install blower fan switch (WP 0172).
Proceed to Test Step 14.
0031-7