TM 5-3805-293-23-2
0022
Table 1. Cab Heating, Air Conditioning, and 12 Volt Power Inverter Troubleshooting Procedures - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
3. Blower Motor Does Not
7. Using digital multimeter, test for
Resistance 5.0 Ohms or Less - Pro-
Turn On In One or More
continuity between HVAC blower
ceed to step 8.
Speeds - Continued
relay socket terminal E17 (WP
Resistance More Than 5.0 Ohms -
0009, Figure 398) and machine
Verify cab ground (WP 0009, Figure
ground.
65) is clean and tight. If cab ground is
Resistance should be less than 5.0
OK, replace cab lower wiring harness
ohms.
(WP 0266).
Proceed to step 19.
8. Turn battery disconnect switch
and ignition switch to the ON posi-
tion (TM 5-3805-293-10).
9. Using digital multimeter, test for
Voltage 18 to 26 Volts - Proceed to
voltage between HVAC blower
step 10.
relay socket terminal E18 (WP
Voltage Less Than 18 Volts - Pro-
0009, Figure 398) and machine
ceed to step 14.
ground.
Voltage should be 18 to 26 volts.
10. Turn ignition switch and battery
disconnect switch to the OFF
position (TM -5-3805-293-10).
11. Install jumper wire between
HVAC blower relay socket termi-
nal E18 (WP 0009, Figure 398)
and terminal C17.
12. Turn battery disconnect switch
and ignition switch to the ON posi-
tion (TM 5-3805-293-10).
13. Verify HVAC blower motor turned
HVAC Blower Motor Turned ON -
ON.
Replace HVAC blower relay (WP
0009, Figure 398).
Proceed to step 19.
HVAC Blower Motor Did Not Turn
On - Replace cab lower wiring har-
ness (WP 0266).
Proceed to step 19.
14. Turn ignition switch and battery
disconnect switch to the OFF
position (TM -5-3805-293-10).
15. Disconnect cab lower wiring har-
ness connector P-C42 (WP 0009,
Figure 90) from cab upper wiring
harness connector R-C3 (WP
0009, Figure 91).
0022-24
