Dodge RAM 1500 1998 Owner's Manual page 2492

DR
HEATING & AIR CONDITIONING (Continued)
Condition
Normal pressures, but A/C
Performance Test air
temperatures at center panel
outlet are too high.
The low side pressure is
normal or slightly low, and the
high side pressure is too low.
The low side pressure is
normal or slightly high, and
the high side pressure is too
high.
The low side pressure is too
high, and the high side
pressure is too low.
Possible Causes
1. Excessive refrigerant oil in
system.
2. Blend door inoperative or
sealing improperly.
3. Blend door actuator faulty
or inoperative.
1. Low refrigerant system
charge.
2. Refrigerant flow through
the accumulator is restricted.
3. Refrigerant flow through
the evaporator coil is
restricted.
4. Faulty compressor.
1. Condenser air flow
restricted.
2. Inoperative cooling fan.
3. Refrigerant system
overcharged.
4. Air in the refrigerant
system.
5. Engine overheating.
1. Accessory drive belt
slipping.
2. Fixed orifice tube not
installed.
3. Faulty compressor.
HEATING & AIR CONDITIONING
Correction
1. See Refrigerant Oil Level in this group.
Recover the refrigerant from the refrigerant
system and inspect the refrigerant oil content.
Restore the refrigerant oil to the proper level, if
required.
2. See Blend Door in this group. Inspect the
blend door for proper operation and sealing and
correct, if required.
3. Perform blend door actuator diagnosis, replace
if faulty.
1. See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.
2. See Accumulator in this group. Replace the
restricted accumulator, if required.
3. See A/C Evaporator in this group. Replace the
restricted evaporator coil, if required.
4. See A/C Compressor in this group. Replace
the compressor, if required.
1. Check the A/C condenser for damaged fins,
foreign objects obstructing air flow through the
condenser fins, and missing or improperly
installed air seals. Refer to Cooling for more
information on air seals. Clean, repair, or replace
components as required.
2. Refer to Cooling for more information. Test the
cooling fan and replace, if required.
3. See Refrigerant System Charge in this group.
Recover the refrigerant from the refrigerant
system. Charge the refrigerant system to the
proper level, if required.
4. See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.
5. Refer to Cooling for more information. Test the
cooling system and repair, if required.
1. Refer to Cooling for more information. Inspect
the accessory drive belt condition and tension.
Tighten or replace the accessory drive belt, if
required.
2. See A/C Orifice Tube in this group. Replace
the liquid line, if required.
3. See A/C Compressor in this group. Replace
the compressor, if required.
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