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
4. Refrigerant Compressor
14. Monitor and record low pressure
A/C Performance Test OK - Remove
Will Not Engage - Con-
and high pressure gauges.
A/C Refrigerant Reclaimer. Trouble-
tinued
shooting complete.
A/C Performance Test Not OK -
Repeat troubleshooting from the
beginning.
Test Step 9. Test Evaporator Tem-
perature Switch Sensing Bulb
(Thermostatic Switch) and Circuits
In Cab Lower Wiring Harness
1. Connect rear air conditioning
wiring harness connector AW-C11
(WP 0009, Figure 259) to
refrigerant compressor thermostat
pull-down resistor (WP 0009,
Figure 258) (WP 0098).
2. Disconnect rear chassis wiring
harness connector FA-C35 (WP
0009, Figure 15) from cab lower
wiring harness connector P-C70
(WP 0009, Figure 16) (WP 0188).
3. Using digital multimeter, test for
Resistance 5.0 Ohms or Less - Pro-
continuity between harness con-
ceed to Test Step 10.
nector P-C70 (WP 0009, Figure
Resistance More Than 5.0 Ohms -
16) terminal 3 and terminal 18.
Proceed to step 4.
Resistance should be less than
5.0 ohms.
4. Disconnect harness connector P-
C16 (WP 0009, Figure 273) from
harness connector CM-C1 (WP
0009, Figure 272) (WP 0294).
5. Using digital multimeter, test for
Resistance 5.0 Ohms or Less -
continuity between harness con-
Replace cab lower wiring harness
nector CM-C1 (WP 0009, Figure
(WP 0188).
272) terminal 2 and terminal 7.
Proceed to step 8.
Resistance should be less than
Resistance More Than 5.0 Ohms -
5.0 ohms.
Proceed to step 6.
6. Remove evaporator temperature
switch sensing bulb from evapo-
rator core (WP 0294).
0022-37