TB 9-2320-302-13&P-3
A/C TROUBLESHOOTING PROCEDURES - CONTINUED
0013 00
MALFUNCTION
CAUSE OR TEST
CORRECTIVE ACTION
A/C SYSTEM PRESSURE DIAGNOSIS
High Side and Low Side Pressure Excessive oil in system.
Restore proper oil level in
1.
Assembly Not Producing Cold
Air.
Moisture in system. Moisture freezes,
2.
High Side Pressure Normal to
High - Low Side Pressure Normal temporarily stopping cycle; normal system
operation returns when ice melts.
to High.
Repair or replace any leaks found in
3.
High Side Pressure Low - Low
system. If no leaks are found, proceed
Side Pressure Low.
to step 2.
2. Incorrect charge.
Refrigerant flow obstructed in receiver/
4.
High Side Pressure Low - Low
dryer.
Side Pressure Zero to Negative -
Frost on Tubes From
Assembly.
1. Internal leak in compressor or
5.
High Side Pressure Low - Low
Pressure Side High.
1. Inspect system for kinked or damaged
6.
High Side Pressure High - Low
00). If no damage is found, proceed
hoses.
Pressure Side Low.
to step 2.
2. Restriction in condenser.
1. Inspect system for kinked or damaged
7.
High Side Pressure High - Low
00). If no damaged hoses are found,
hoses.
Pressure Side High - Low Side
proceed to step 2.
Lines Hot to Touch.
Repair as necessary.
8.
High Side Pressure High - Low
Pressure Side High.
2. Engine cooling fan not working properly. Troubleshoot engine fan. Proceed to
3. Refrigerant system overcharged.
Recover refrigerant and recharge
4. Expansion valve not operating correctly. Replace expansion valve (WP 0017
END OF WORK PACKAGE