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 blower
Not Operate at One or More
Replace HVAC blower motor (WP
motor wiring harness connector
Speeds - Continued
0349).
(WP 0007, Figure 148) terminal D
Install blower fan switch (WP 0172).
and machine ground. Resistance
Proceed to Test Step 14.
should be 5.0 ohms or less.
Resistance Greater Than 5.0 Ohms -
Verify that cab ground (Figure 5, Item 1)
is clean and tight. If cab ground is OK,
replace cab wiring harness (WP 0181).
Install blower fan switch (WP 0172).
Proceed to Test Step 14.
Figure 5. Cab Ground.
0031
Test Step 8. Test Blower Fan Switch
Voltage Supply for an Open Circuit.
1. Remove front instrument panel
right-side cover (WP 0176).
2. Disconnect side console wiring
harness connector (WP 0007, Fig-
ure 24) from rear main chassis wir-
ing harness connector (WP 0007,
Figure 25) (WP 0170).