TM 5-3805-291-23-1
TROUBLESHOOTING WITHOUT A DIAGNOSTIC CODE - CONTINUED
0008 00
Table 8. AC System Troubleshooting - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1. Check low and high pressure gage
1. If low pressure gage reading is above
6.
Compressor Will Not
during operation of AC.
normal and high pressure gage reading
Engage. Air Flow to
is below normal, go to Test 2.
Operator's Compartment is
2. If readings are not as specified, exit this
Warm.
test.
2. Check AC compressor.
1. If problem is loose wire on switch or a
(a) Check wire connectors on
loose wire on magnetic clutch, make
thermostatic switch and on
repairs that are needed or replace
compressor clutch.
compressor (WP 0221 00).
(b) Check for insulation that is
2. If wires to clutch were damaged,
broken.
damaged wires can cause switch to
(c) Check for clutch coil resistance of
remain open. Make needed repairs to
17.6+/- 0.6 Ohms with a
damaged wires.
3. After system is charged, operate for a
(d) Check for proper electrical ground
minimum of 10 minutes (TM 5-3805-
291-10) and perform Performance
at magnetic clutch.
Checks for AC System (WP 0018 00) to
(e) Touch two wires on switch
together. Check for proper
verify correct operation of AC system.
operation of magnetic clutch.
4. If problem still exists, go to Test 3.
3. Refer to Electrical System
If problem still exists, go to Test 4.
Troubleshooting (Table 2 in this work
package) to check the AC control
system.
4. Check for lost charge of refrigerant in
1. If capillary tube has no charge or switch
capillary tube.
remains open, problem is in
thermostatic switch, replace
compressor (WP 0221 00).
2. After system is charged, operate for a
minimum of 10 minutes (TM 5-3805-
291-10) and perform Performance
Checks for AC System (WP 0018 00) to
verify correct operation of AC system.
N OT E
7.
Compressor Continues to
Cycle or Clutch Will Not
Cause of problem may be one of following conditions: low charge, over-
Disengage. Air Flow to
charge, or evaporator freeze-up.
Operator's Compartment is
Very Cold or Air Flow May
be Restricted Completely at
Times.
1. Check low and high pressure gage
1. If low pressure gage reading is below
during operation of AC.
normal and high pressure gage reading
is below normal, go to Test 2.
2. If readings are not as specified, exit this
test.
