Insufficient Cooling

TROUBLE DIAGNOSIS

Insufficient Cooling

SYMPTOM: Insufficient cooling

INSPECTION FLOW


1. CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE DECREASE

1.Turn temperature control dial counterclockwise to maximum cold position.
2.Check for cold air at discharge air outlets.
Is the inspection results normal?
YES- GO TO 3.
NO- GO TO 2.

2. CHECK FOR ANY SYMPTOMS

Perform a complete operational check for any symptoms. Operational Check.
Does another symptom exist?
YES- How To Perform Trouble Diagnosis For Quick And Accurate Repair.
NO- System OK.

3. CHECK FOR SERVICE BULLETINS

Check for any service bulletins.
- GO TO 4.

4. CHECK COMPRESSOR DRIVE BELT TENSION

Check compressor belt tension. Refer to Procedures.
OK or NG
OK- GO TO 5.
NG- Adjust or replace compressor belt. Removal And Installation.

5. CHECK AIR MIX DOOR CABLE

Check and verify air mix door cable operation. Air Mix Door Cable Adjustment.
Does air mix door operate correctly?
YES- GO TO 6.
NO- Repair or replace as necessary.

6. CHECK COOLING FAN MOTOR OPERATION

Check and verify cooling fan motor for smooth operation. P1217.
Does cooling fan motor operate correctly?
YES- GO TO 7.
NO- Check cooling fan motor. P1217.

7. CHECK FOR EVAPORATOR FREEZE UP

Start engine and run A/C. Check for evaporator freeze up.
Does evaporator freeze up?
YES- Perform diagnostic work flow. Refer to "DIAGNOSTIC WORK FLOW".
NO- GO TO 8.

8. CHECK REFRIGERANT PRESSURE

Check refrigerant pressure with manifold gauge connected. Refer to "PERFORMANCE CHART".
OK or NG
OK- GO TO 9.
NG- Perform diagnostic work flow. Refer to "DIAGNOSTIC WORK FLOW".

9. CHECK AIR DUCTS

Check ducts for air leaks.
OK or NG
OK- If the symptom still exists, perform a complete operational check. Operational Check. If other symptoms exist, How To Perform Trouble Diagnosis For Quick And Accurate Repair.
NG- Repair air leaks.

DIAGNOSTIC WORK FLOW






















PERFORMANCE CHART

Test Condition
Testing must be performed as follows:






TEST READING

Recirculating-to-discharge Air Temperature Table





Ambient Air Temperature-to-operating Pressure Table





*1: With blower control dial in the "1" position
*2: With blower control dial in the "4" position.

TROUBLE DIAGNOSIS FOR ABNORMAL PRESSURE

Whenever systems high and/or low side pressure(s) is/are abnormal, diagnose using a manifold gauge. The marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air temperature-to-operating pressure table).
Both High- and Low-pressure Sides are Too High





High-pressure Side is Too High and Low-pressure Side is Too Low





High-pressure Side is Too Low and Low-pressure Side is Too High





Both High- and Low-pressure Sides are Too Low





Low-pressure Side Sometimes Becomes Negative





Low-pressure Side Becomes Negative