NO.8 AIR FROM FRONT/REAR VENTS NOT COLD ENOUGH

id070300901200

8 | Air from front/rear vents not cold enough
DESCRIPTION | • Malfunction in A/C basic system • Magnetic clutch operates but A/C system malfunctions
POSSIBLE CAUSE | Note • If the engine coolant temperature increases due to a cooling system malfunction, the fail-safe function disables the A/C operation. • Drive belt malfunction • Refrigerant pressure sensor malfunction • Cooling fan system malfunction • Condenser or related part malfunction • A/C unit or condenser malfunction • Receiver/drier or expansion valve malfunction (valve closes too much) • Malfunction in refrigerant lines • A/C compressor system malfunction, insufficient compressor oil • Over filling of compressor oil, malfunction in expansion valve or A/C unit air mix link system • Evaporator temperature sensor malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
--- | --- | ---
1 | INSPECT CLIMATE CONTROL UNIT FOR DTC • Retrieve the climate control unit DTC using the A/C Operation Check Mode. • Are there DTC displayed? | Yes | Go to the applicable DTC troubleshooting procedures. (See DIAGNOSTIC TROUBLE CODE NUMBER INSPECTION.)
No | Go to the next step.
2 | INSPECT REFRIGERANT PRESSURE TO LOCATE MALFUNCTION • Perform refrigerant pressure check. (See REFRIGERANT PRESSURE CHECK.) • Is the refrigerant pressure normal? | Yes | Go to the next step.
No | Record the inspection result. • If the refrigerant high-pressure and low-pressure values are both high, go to Step 6. • If the refrigerant high-pressure and low-pressure values are approximately the same, go to Step 9. • If the refrigerant high-pressure and low-pressure values are both low, go to Step 11. • If there is a vacuum on the low pressure side and extremely low pressure on the high pressure side, go to Step 17. • If there is low pressure on the high pressure side and high pressure on the low pressure side, replace the A/C compressor, then go to Step 21. (See A/C COMPRESSOR REMOVAL/INSTALLATION.) • If the refrigerant pressure is other than above condition, go to Step 19.
3 | INSPECT REFRIGERANT SYSTEM PERFORMANCE • Perform the refrigerant system performance test on the front or rear A/C from the side which cool air does not blow. (See REFRIGERANT SYSTEM PERFORMANCE TEST.) • Is the operation normal? | Yes | Operation is normal (Recheck malfunction symptoms.).
No | Go to the next step.
4 | INSPECT DRIVE BELT • Inspect the drive belt. (See DRIVE BELT INSPECTION [MZI-3.7].) • Is it normal? | Yes | Go to the next step.
No | Adjust or replace the drive belt, then go to the next step. (See DRIVE BELT REMOVAL/INSTALLATION [MZI-3.7].)
5 | INSPECT REFRIGERANT PRESSURE SENSOR • Inspect the refrigerant pressure sensor. (See REFRIGERANT PRESSURE SENSOR INSPECTION.) • Is it normal? | Yes | Go to the next step.
No | Repair or replace malfunctioning part according to inspection result, then go to Step 21.
6 | INSPECT COOLING FAN OPERATION • Verify the cooling fan operation. (See FAN CONTROL MODULE INSPECTION [MZI-3.7].) • Is the cooling fan operation normal? | Yes | Go to the next step.
No | Repair or replace the malfunctioning location according to the inspection results. Then go to Step 21.
7 | VISUALLY INSPECT CONDENSER • Is the condenser fin clogged or obstructed by foreign material? | Yes | Remove the foreign material. Repair the condenser fin. Then go to Step 21.
No | Go to the next step.
8 | CHECK REFRIGERATION SYSTEM FOR OVERCHARGE OR AIR CONTAMINATION • Is the low side line hot to the touch? | Yes | Recover refrigerant. Evacuate system for one hour. Refill with correct amount of refrigerant, and go to step 21.
No | Recover refrigerant, evacuate for 15 minutes, refill with correct amount and go to step 21.
9 | CHECK TO SEE WHETHER MALFUNCTION IS IN EXPANSION VALVE OR ELSEWHERE • Compare the refrigerant pressure of the low pressure side with the high pressure side at Step 2. • Is there little difference between the high pressure side and low pressure side readings (refer to graph in REFRIGERANT PRESSURE CHECK procedure)? (See REFRIGERANT PRESSURE CHECK.) | Yes | Replace the expansion valve. After performing the following servicing, go to Step 21. • Adjust the compressor oil to the specified level. • After discharging, charge with new refrigerant to the specified level.
No | Go to the next step.
10 | INSPECT AIR MIX DOOR RELATED PART INSTALLATION • Measure the climate control unit terminal 2F and 2G voltage when the temperature control dials are set to MAX COLD and MAX HOT by control panel. • Are voltages normal? | Yes | Adjust the compressor oil to the specified amount, then go to Step 21. (See A/C COMPRESSOR REMOVAL/INSTALLATION.)
No | • Inspect the air mix link, air mix crank, and air mix rod of the A/C unit correctly and securely installed to their positions. • Repair or install correctly for suspect part according to inspection result, then go to next Step. (See FRONT A/C UNIT DISASSEMBLY/ASSEMBLY.) (See REAR A/C UNIT DISASSEMBLY/ASSEMBLY.)
11 | INSPECT BLOWER UNIT FOR BLOCKAGE • Is the blower unit intake and air filter of the front or rear A/C from the side which cool air does not blow clogged? | Yes | Remove the cause of the clogging. Replace the air filter if it is clogged. (See AIR FILTER REMOVAL/INSTALLATION.) Then go to Step 21.
No | Go to the next step.
12 | CHECK TO SEE WHETHER MALFUNCTION IS REFRIGERANT LINE LEAKAGE OR ELSEWHERE • Verify if there is gas leakage from the system hoses using the gas leak tester. • Is there gas leakage? | Yes | If there is leakage from a system hose connection area, go to Step 14. If there is leakage other than from a system hose connection area, go to Step 16.
No | Go to the next step.
13 | VISUALLY INSPECT REFRIGERANT LINE • Is a system hose crushed? | Yes | Replace the crushed system hose. (See REFRIGERANT LINE REMOVAL/INSTALLATION.) After performing the following servicing, go to Step 21. • Adjust the compressor oil to the specified level. • After discharging, charge with new refrigerant to the specified level.
No | Go to Step 20.
14 | CHECK TO SEE WHETHER MALFUNCTION IS IN REFRIGERANT LINE JOINT LOOSE OR O-RING • Tighten the system hose connection area to the specified torque. (See REFRIGERANT LINE REMOVAL/INSTALLATION.) • Has the leakage stopped? | Yes | Go to the next step.
No | Go to Step 16.
15 | VISUALLY INSPECT REFRIGERANT LINE • Is a system hose crushed? | Yes | Replace the crushed system hose. (See REFRIGERANT LINE REMOVAL/INSTALLATION.) After performing the following servicing, go to Step 21. • Adjust the compressor oil to the specified level. • After discharging, charge with new refrigerant to the specified level.
No | Adjust the compressor oil to the specified amount, then go to Step 21. (See A/C COMPRESSOR REMOVAL/INSTALLATION.)
16 | VISUALLY INSPECT REFRIGERANT LINE • Is a system hose crushed? | Yes | Replace the O-ring of the leaking area. Replace the crushed system hose. (See REFRIGERANT LINE REMOVAL/INSTALLATION.) After performing the following servicing, go to Step 21. • Adjust the compressor oil to the specified level. • After discharging, charge with new refrigerant to the specified level.
No | Replace the O-ring of the leaking area. After performing the following servicing, go to Step 21. • Adjust the compressor oil to the specified level. • After discharging, charge with new refrigerant to the specified level.
17 | CHECK TO SEE WHETHER MALFUNCTION IS WATER IN REFRIGERANT SYSTEM OR ELSEWHERE • Does the refrigerant pressure on the low pressure side vary between the vacuum and normal range? | Yes | Replace the condenser. (Water in refrigerant system) (See CONDENSER REMOVAL/INSTALLATION.) Then go to Step 21.
No | Go to the next step.
18 | CHECK TO SEE WHETHER MALFUNCTION IS IN RECEIVER DRYER FILTER OR EXPANSION VALVE • Remove the expansion valve of the front or rear A/C from the side which cool air does not blow and verify its condition. • Is there refrigerant leakage or valve clogging? | Yes | If there is foreign matter clogging the valve: • Remove the foreign matter. If there is refrigerant leakage or clogging: • Replace the expansion valve. Perform discharge, charge with new refrigerant, and then go to Step 21.
No | Replace the condenser (Receiver/Dryer filter is clogged.). (See CONDENSER REMOVAL/INSTALLATION.) Then go to Step 21.
19 | INSPECT EVAPORATOR TEMPERATURE SENSOR • Inspect the evaporator temperature sensor of the front or rear A/C from the side which cool air does not blow. (See FRONT EVAPORATOR TEMPERATURE SENSOR INSPECTION.) (See REAR EVAPORATOR TEMPERATURE SENSOR INSPECTION.) • Is it normal? | Yes | Verify the evaporator temperature sensor position. (See FRONT A/C UNIT DISASSEMBLY/ASSEMBLY.) (See REAR A/C UNIT DISASSEMBLY/ASSEMBLY.) Then go to Step 21.
No | Replace the evaporator temperature sensor, then go to Step 21. (See FRONT A/C UNIT DISASSEMBLY/ASSEMBLY.) (See REAR A/C UNIT DISASSEMBLY/ASSEMBLY.)
20 | INSPECT AIR MIX DOOR RELATED PART INSTALLATION • Measure the climate control unit terminal 2F and 2G voltage when the temperature control dials are set to MAX COLD and MAX HOT by control panel. • Are voltages are normal? | Yes | Go to the next step.
No | • Inspect the air mix link, air mix crank, and air mix rod of the A/C unit correctly and securely installed to their positions. • Repair or install correctly for suspect part according to inspection result, then go to next Step. (See FRONT A/C UNIT DISASSEMBLY/ASSEMBLY.) (See REAR A/C UNIT DISASSEMBLY/ASSEMBLY.)
21 | VERIFY THAT MALFUNCTION SYMPTOM DOES NOT OCCURS AFTER REPAIR • If the refrigerant discharged during inspection has not been recharged, discharge and charge with new refrigerant to the specified level. • Does cool air blow out? (Are results of refrigerant system performance test normal?) | Yes | Troubleshooting completed. Explain repairs to customer.
No | Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.