Diagnostic Starting Point - Heating, Ventilation and Air Conditioning
The HVAC system is divided into 2 separate sections. The first, heating, ventilation, and air conditioning, has all procedures that pertain to an HVAC component or function that is not specifically associated with the manual control system. The second, HVAC Systems - Manual, has all procedures specific to the Manual control system.
Begin the system diagnosis with the Diagnostic System Check - Vehicle in Vehicle DTC Information.
The Diagnostic System Check will provide the identification of the control modules which command the system.
The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.
Review the Description and Operation information to help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the Description and Operation information will also help you determine if the condition described by the customer is normal operation. The HVAC Description and Operation information is divided into
- «Air Delivery Description and Operation»(ref-196990-S08986362412005101000000) in HVAC Systems - Manual
- «Air Temperature Description and Operation»(ref-196990-S13132004112005101000000) in HVAC Systems - Manual
The Air Delivery Description and Operation contains the following topics
- Air speed
- Air distribution
The Air Temperature Description and Operation contains the following topics
- Heater Mode
- A/C Mode
- A/C cycle
Refrigerant Leak Testing
Tools Required
- J 39400-A Halogen Leak Detector. See «Special Tools»(ref-197012-S41925114452005101000000) .
- J 41447 R 134a A/C Tracer Dye-Box of 24. See «Special Tools»(ref-197012-S41925114452005101000000) .
- J 42220 Universal 12V Leak Detection Lamp. See «Special Tools»(ref-197012-S41925114452005101000000) .
- J 46297 A/C Dye Injector Kit. See «Special Tools»(ref-197012-S41925114452005101000000) .
- J 46297-12 Replacement Dye Cartridges. See «Special Tools»(ref-197012-S41925114452005101000000) .
| IMPORTANT | Saturn vehicles are now manufactured with fluorescent dye installed directly into the A/C system. |
The preferred method of leak testing is with the use of fluorescent dye. J 41447 is the only fluorescent dye approved by Saturn. See Special Tools .
The fluorescent dye mixes and flows with the PAG oil throughout the refrigerant system.
Verifying some passive leaks may require using the J 39400-A , even though the A/C system contains fluorescent dye. See Special Tools .
The only time that adding additional fluorescent dye is required is after flushing the A/C system.
Air Conditioning (A/C) System Performance Test (2.2 L61)
This test measures the operating efficiency of the A/C system under the following conditions
- The current ambient air temperature
- The current relative humidity
- The high side pressure of the A/C system
- The low side pressure of the A/C system
- The temperature of the air being discharged into the passenger compartment
Air Conditioning (A/C) System Performance Test (2.0 LSJ )
This test measures the operating efficiency of the A/C system under the following conditions
- The current ambient air temperature
- The current relative humidity
- The high side pressure of the A/C system
- The low side pressure of the A/C system
- The temperature of the air being discharged into the passenger compartment
Air Conditioning (A/C) Diagnostics - Pressure Zone A
| Step | Action | Value | Yes | No |
|---|---|---|---|---|
| DEFINITION: The high and low side pressures may be normal or slightly less than normal. Air Delivery Concern Slight Refrigerant Under Charge Refrigerant Contamination | ||||
| 1 | Were you sent here from the A/C System Performance Test? | Go to Step 2 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) | |
| 2 | Refer to the panel air outlet temperatures recorded during the A/C system performance test. Does the discharge air temperature between the right and left center panel outlets vary by more than 4°C (5°F)? | Go to Step 7 | Go to Step 3 | |
| 3 | Did the customer mention that the A/C system output temperatures are good at first, but then turn warm during extended drives? | Go to Step 4 | Go to Step 5 | |
| 4 | Increase engine speed to 2,000 RPM. During extended operation of the A/C system, does the low side pressure decrease, possibly accompanied by heavy frost on the liquid line between the expansion device and the evaporator? | Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D | Go to Step 5 | |
| 5 | Refer to the pressures recorded during the A/C system performance test. Inspect for the following conditions: CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. The high side pressure is slightly greater than the specified pressure ranges but still within Zone A on the A/C Pressure-Zone Classification Chart in the A/C System Performance Test. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . The discharge line is hot. The suction line is cool. Do the listed conditions exist? | Go to Step 7 | Go to Step 6 | |
| 6 | Refer to the pressures recorded during the A/C system performance test. Inspect for the following conditions: The low side pressure is slightly lower than the specified pressure ranges but still within Zone A on the A/C Pressure-Zone Classification Chart in the A/C System Performance Test. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . The discharge line is warm-to-hot. The suction line is cool-to-warm. Do the listed conditions exist? | Go to Step 8 | Go to Too Hot in Vehicle in HVAC Systems - Manual | |
| 7 | The A/C system may be undercharged. Leak test A/C system. Refer to Leak Testing . Recharge the A/C system to specifications. Refer to Refrigerant Recovery and Recharging . Is the repair complete? | Go to Step 14 | ||
| 8 | The A/C system may be contaminated. View the J 43600 ACR 2000 information screen for detection of foreign gases in the A/C system. See Special Tools . Do foreign gases exist? | Go to Step 9 | Go to Step 10 | |
| 9 | Evacuate the A/C system to a scavenging tank. Refer to Refrigerant Recovery and Recharging . Recharge the A/C system to specifications. Is the repair complete? | Go to Step 14 | ||
| 10 | The A/C system may contain too much moisture or air. Evacuate and recharge the A/C system to specifications. Refer to Refrigerant Recovery and Recharging . Operate the A/C system and inspect the panel outlet air temperatures. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . Are the panel outlet temperatures within the specified ranges of the A/C Performance Test Table? | Go to Step 15 | Go to Step 11 | |
| 11 | The A/C system may contain too much refrigerant oil. IMPORTANT: Operate the A/C system on low, in order to enhance oil flow to the high side of the system. Operate the A/C system with the engine at idle speed and the blower speed on low for approximately 15 minutes. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging . Measure the oil recovered by the J 43600 . See Special Tools . Was the amount greater than the specified value? | 60 ml (2 oz) | Go to Step 12 | Go to Step 13 |
| 12 | Recharge the A/C system but do not add the amount of oil recovered by the J 43600 . See Special Tools . Refer to Refrigerant Recovery and Recharging . Are the repairs complete? | Go to Step 14 | ||
| 13 | Recharge the A/C system but do not add the amount of oil recovered by the J 43600 . See Special Tools . Refer to Refrigerant Recovery and Recharging . Are the repairs complete? | Go to Step 14 | ||
| 14 | Record the low and high side pressures and the I/P panel outlet air temperature. Compare the panel outlet temperatures to those listed in the A/C System Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . Are the high and low side pressures and I/P panel outlet temperatures within specifications? | Go to Step 15 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) | |
| 15 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Symptoms - HVAC Systems - Manual | |
| CAUTION |
|---|
| Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. |
| IMPORTANT |
|---|
| Operate the A/C system on low, in order to enhance oil flow to the high side of the system. |
Air Conditioning (A/C) Diagnostics - Pressure Zone A
Air Conditioning (A/C) Diagnostics - Pressure Zone B
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: The low side pressure is higher than normal and the high side pressure is lower than normal. Malfunctioning A/C Compressor Refrigerant Under Charge | |||
| 1 | Were you sent here from the A/C System Performance Test? | Go to Step 2 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) |
| 2 | After continued operation of the A/C system, do the low and the high side pressures equalize or become static? | Go to Step 5 | Go to Step 3 |
| 3 | Refer to the pressures recorded during the A/C System Performance Test. Inspect for the following conditions: CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. The low side pressure is equal to or greater than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . The high side pressure is less than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . The low side refrigerant line at the compressor feels cool-to-warm. The high side refrigerant line at the compressor feels warm-to-hot. Do the listed conditions exist? | Go to Step 5 | Go to Step 4 |
| 4 | Refer to the pressures recorded during the A/C System Performance Test. Inspect for the following conditions: CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. The low side pressure is greater than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . The high side pressure is less than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . The low side refrigerant line at the compressor feels warm. The high side refrigerant line at the compressor feels warm to hot. Do the listed conditions exist? | Go to Step 5 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) |
| 5 | The A/C system has a low refrigerant charge. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the procedure complete? | Go to Step 6 | |
| 6 | Record the low and the high side pressures as well as the IP panel outlet air temperature after you perform the repairs. Compare the pressures and the panel outlet temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . Are the readings within the specified ranges found on the A/C Performance Chart? | Go to Step 13 | Go to Step 7 |
| 7 | The A/C compressor is malfunctioning. Remove the expansion device and inspect for contamination. Refer to Thermal Expansion Valve Replacement . Did you find metal flakes on the expansion device? | Go to Step 9 | Go to Step 8 |
| 8 | Inspect the expansion device for a brown, powdery residue indicating desiccant in the A/C system. Is a brown, powdery residue present? | Go to Step 11 | Go to Step 12 |
| 9 | Remove the compressor hose from the compressor. Refer to Compressor Hose Assembly Replacement (2.2L (L61)) or Compressor Hose Assembly Replacement (2.0 L (LSJ)) . Inspect for metal flake contamination at the line connections and the compressor ports. Is metal flake contamination present? | Go to Step 10 | Go to Step 12 |
| 10 | Replace the A/C compressor. Refer to Compressor Replacement (2.2L (L61)) or Compressor Replacement (2.0L (LSJ)) . Replace the A/C Refrigerant Filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Replace the thermal expansion valve. Refer to Thermal Expansion Valve Replacement . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete? | Go to Step 13 | |
| 11 | Replace the thermal expansion valve. Refer to Thermal Expansion Valve Replacement . Replace the A/C Refrigerant Filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Replace the A/C compressor. Refer to Compressor Replacement (2.2L (L61)) or Compressor Replacement (2.0L (LSJ)) . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete? | Go to Step 13 | |
| 12 | Replace the A/C compressor. Refer to Compressor Replacement (2.2L (L61)) or Compressor Replacement (2.0L (LSJ)) . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete? | Go to Step 13 | |
| 13 | Operate the system in order to verify the repair Did you find and correct the condition? | System OK | Go to Symptoms - HVAC Systems - Manual |
| CAUTION |
|---|
| Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. |
| CAUTION |
|---|
| Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. |
Air Conditioning (A/C) Diagnostics - Pressure Zone B
Air Conditioning (A/C) Diagnostics - Pressure Zone C
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: The low and the high side pressures are both higher than normal. Restricted Condenser Air Flow Cooling Fan Malfunction Expansion Device Malfunction | |||
| 1 | Were you sent here from the A/C System Performance Test? | Go to Step 2 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) |
| 2 | Start the engine. Turn ON the A/C. Inspect for proper cooling fan operation. Refer to Cooling System Description and Operation in Engine Cooling. Are the cooling fans ON and operating properly? | Go to Step 3 | Go to Step 5 |
| 3 | Visually inspect for the following conditions: Damaged condenser cooling fins Missing or misaligned air baffles Restricted air flow Do any of these conditions exist? | Go to Step 4 | Go to Step 6 |
| 4 | Repair the air flow restriction. Is the repair complete? | Go to Step 9 | |
| 5 | Repair the fault to the cooling fan operation. Refer to Cooling Fan Inoperative (2.2L (L61)) or Cooling Fan Inoperative (2.0L (LSJ)) in Engine Cooling. Is the repair complete? | Go to Step 9 | |
| 6 | CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Feel the liquid line on both sides of the expansion device.Are the temperatures on both sides of the expansion device similar? | Go to Step 7 | Go to Step 8 |
| 7 | Replace the damaged or faulty thermal expansion valve. Refer to Thermal Expansion Valve Replacement . Is the repair complete? | Go to Step 9 | |
| 8 | Air is in the refrigerant system, or the system is overcharged. Refer to the view screen on J 43600 ACR 2000 for foreign gas content in the refrigerant. See Special Tools . Recover and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the repair complete? | Go to Step 9 | |
| 9 | Record the low and high side pressures and the IP panel outlet air temperature after you have performed the repairs. Compare the pressures and the panel outlet temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . Are the readings within the specified ranges listed in the A/C Performance Chart? | Go to Step 10 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) |
| 10 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Symptoms - HVAC Systems - Manual |
| CAUTION |
|---|
| Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. |
Air Conditioning (A/C) Diagnostics - Pressure Zone C
Air Conditioning (A/C) Diagnostics - Pressure Zone D
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: The low side pressure is lower than normal and the high side pressure is higher than normal. A restriction in the A/C system. Debris in the system. | |||
| 1 | Were you sent here from the A/C System Performance Test? | Go to Step 2 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) |
| 2 | CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Feel the liquid line before the expansion device.Is the liquid line cold before the expansion device? | Go to Step 3 | Go to Step 8 |
| 3 | Feel along the surfaces of the following high side components: The compressor discharge hose The condenser The liquid line between the condenser and the expansion device Did you detect an abrupt drop in temperature along the surfaces of any of the listed components? | Go to Step 7 | Go to Step 4 |
| 4 | Feel the liquid line at the expansion device location for extreme cold, possibly accompanied by heavy frost. Feel along the liquid line beyond the expansion device location for warm temperature. Is the liquid line extremely cold at the expansion device location and warm beyond the expansion device location? | Go to Step 11 | Go to Step 5 |
| 5 | Feel along the surfaces of the following low side components: The evaporator outlet tube between the evaporator core and the compressor suction hose The compressor suction hose Did you feel an abrupt temperature change along the surfaces of any of the listed components? | Go to Step 7 | Go to Step 6 |
| 6 | Feel along the surfaces of the low and the high side components: The evaporator outlet tube between the evaporator core and the compressor The compressor suction hose The compressor discharge hose The condenser The evaporator inlet tube between the condenser and the expansion device Are the temperatures of these components only mildly warm? | Go to Step 14 | Go to Step 8 |
| 7 | Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Remove the restriction from the component, or replace the component which produced an abrupt temperature drop. Is the repair complete? | Go to Step 9 | |
| 8 | Recover the refrigerant and evacuate the system. Refer to Refrigerant Recovery and Recharging . Record the weight of the recovered refrigerant. Compare the weight of the recovered refrigerant with the system capacity. Refer to Refrigerant System Capacities . Is the weight of the recovered refrigerant charge greater than 75 percent of the total system capacity? | Go to Step 9 | Go to Step 10 |
| 9 | Recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the cooling performance improved? | Go to Step 21 | Go to Step 10 |
| 10 | Leak test the system. Refer to Leak Testing . Repair any leaks. Is the repair complete? | Go to Step 21 | |
| 11 | The A/C refrigerant filter or expansion device is restricted. Replace the A/C refrigerant filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Replace the expansion device. Refer to Thermal Expansion Valve Replacement . Are metal flakes present? | Go to Step 12 | Go to Step 13 |
| 12 | Remove the compressor hose assembly from the vehicle. Refer to Compressor Hose Assembly Replacement (2.2L (L61)) or Compressor Hose Assembly Replacement (2.0 L (LSJ)) . Inspect the hose for debris by blowing shop air through one end of the hose while covering the other end with a shop towel. Observe the amount of debris collected in the shop towel. Did a large amount of debris collect in the shop towel? | Go to Step 18 | Go to Step 20 |
| 13 | If the expansion device was restricted with a brown or black residue, perform the following procedure: Replace the condenser. Refer to Condenser Replacement (2.2L (L61)) or Condenser Replacement (2.0L (LSJ)) . Are the repairs complete? | Go to Step 21 | |
| 14 | Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Disconnect the compressor hose from the compressor. Refer to Compressor Hose Assembly Replacement (2.2L (L61)) or Compressor Hose Assembly Replacement (2.0 L (LSJ)) . Inspect for the presence of debris in the compressor suction port. Is debris present in the compressor suction port? | Go to Step 15 | Go to Step 19 |
| 15 | Remove the debris from the suction port. Inspect the A/C refrigerant filter for damage or debris. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Inspect the expansion device for damage or debris. Refer to Thermal Expansion Valve Replacement . Did you find evidence of damage or debris? | Go to Step 17 | Go to Step 16 |
| 16 | If the A/C refrigerant filter or expansion device does not show any signs of damage or debris, perform the following procedure: Remove the compressor hose assembly from the vehicle. Refer to Compressor Hose Assembly Replacement (2.2L (L61)) or Compressor Hose Assembly Replacement (2.0 L (LSJ)) . Inspect the hose for debris by blowing shop air through one end of the hose while covering the other end with a shop towel. Observe the amount of debris collected in the shop towel. Did a large amount of debris collect in the shop towel? | Go to Step 18 | Go to Step 19 |
| 17 | Replace the A/C refrigerant filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Replace the expansion device. Refer to Thermal Expansion Valve Replacement . If the A/C refrigerant filter or expansion device was restricted, observe the type of debris present. Are metal flakes present? | Go to Step 12 | Go to Step 13 |
| 18 | If a large amount of debris was collected in the shop towel from the suction hose, perform the following procedure: Replace the condenser. Refer to Condenser Replacement (2.2L (L61)) or Condenser Replacement (2.0L (LSJ)) . Is the repair complete? | Go to Step 19 | |
| 19 | Install the compressor hose assembly. Refer to Compressor Hose Assembly Replacement (2.2L (L61)) or Compressor Hose Assembly Replacement (2.0 L (LSJ)) . Recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Are the repairs complete? | Go to Step 21 | |
| 20 | Install the compressor hose assembly. Refer to Compressor Hose Assembly Replacement (2.2L (L61)) or Compressor Hose Assembly Replacement (2.0 L (LSJ)) . Recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Are the repairs complete? | Go to Step 21 | |
| 21 | Record the low and the high side pressures and the panel outlet air temperature after you perform the repairs. Compare the pressures and the panel outlet temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) . Are the readings within the specified ranges as shown on the A/C Performance Chart? | Go to Step 22 | Go to Air Conditioning (A/C) System Performance Test (2.2 L61) or Air Conditioning (A/C) System Performance Test (2.0 LSJ ) |
| 22 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Symptoms - HVAC Systems - Manual |
| CAUTION |
|---|
| Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. |
Air Conditioning (A/C) Diagnostics - Pressure Zone D
Heating Performance Diagnostic
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Heating system performance. | |||
| 1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual |
| 2 | Start the engine. Allow the engine to idle. Does the engine reach a normal operating temperature? | Go to Step 3 | Go to Step 9 |
| 3 | Allow the engine to idle. Select the FLOOR mode. Select the minimum blower speed. Select the warmest temperature setting. Feel the temperature of the inlet and outlet heater hoses at the heater core. Does the inlet heater hose feel warmer than the outlet heater hose? | Go to Step 7 | Go to Step 4 |
| 4 | Install a thermometer into the center instrument panel (l/P) PANEL air outlet. Secure a thermometer to the heater core outlet hose. Select the PANEL mode. Select the maximum blower speed. Select the warmest temperature setting. Record the temperature at the following locations: The center I/P PANEL air outlet The heater core outlet hose Compare the recorded temperatures. Are the two temperature readings about equal? | Go to Step 5 | Go to Step 6 |
| 5 | Inspect and repair the following areas of the vehicle for cold air leaks: The cowl The recirculation door The HVAC module case Perform the necessary repairs. Are the repairs complete? | Go to Step 10 | |
| 6 | Inspect the temperature door operation. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information. Perform any necessary repairs. Are the repairs complete? | Go to Step 10 | |
| 7 | Turn OFF the engine. Backflush the heater core. Start the engine. Select the FLOOR mode. Select the minimum blower speed. Select the warmest temperature setting. Feel the temperature of the inlet and outlet heater hoses at the heater core. Does the inlet heater hose feel warmer than the outlet heater hose? | Go to Step 8 | Go to Step 10 |
| 8 | Replace the heater core. Refer to Heater Core Replacement . Is the repair complete? | Go to Step 10 | |
| 9 | Repair the low engine temperature concern. Refer to Engine Fails To Reach Normal Operating Temperature in Engine Cooling. Is the repair complete? | Go to Step 10 | |
| 10 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 |
Heating Performance Diagnostic
Noise Diagnosis - Blower Motor
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Noise originating from the blower motor. | |||
| 1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual in HVAC Systems-Manual |
| 2 | Inspect the air inlet grille for debris. Is debris present? | Go to Step 8 | Go to Step 3 |
| 3 | Sit inside the vehicle. Close the vehicle doors and windows. Turn ON the ignition, with the engine OFF. Cycle the blower motor through all of the speeds and modes in order to determine where and when the noise occurs. Is a noise evident during the blower operation? | Go to Step 4 | Go to Step 11 |
| 4 | Inspect for excessive vibration at each blower motor speed by feeling the blower case. Is excess vibration present? | Go to Step 6 | Go to Step 5 |
| 5 | Listen to the blower motor at each speed. Is the blower motor making a squeaking or chirping noise? | Go to Step 9 | Go to Step 11 |
| 6 | Remove the blower motor. Refer to Blower Motor Replacement . Inspect the blower motor impeller for deposits of foreign material. Inspect the blower motor for deposits of foreign material. Did you find any foreign material on the blower motor or blower motor impeller? | Go to Step 8 | Go to Step 7 |
| 7 | Inspect the blower motor for the following conditions: Cracked blades A loose impeller retainer Improper impeller alignment Did you find any of these conditions? | Go to Step 9 | Go to Step 10 |
| 8 | Remove the foreign material. Is the action complete? | Go to Step 10 | |
| 9 | Replace the blower motor. Refer to Blower Motor Replacement . Is the repair complete? | Go to Step 11 | |
| 10 | Install the blower motor. Refer to Blower Motor Replacement . Is the action complete? | Go to Step 11 | |
| 11 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 |
Noise Diagnosis - Blower Motor
Noise Diagnosis - Air Conditioning (A/C) System
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Noise originating from the A/C compressor, drive belt or the A/C lines. | |||
| 1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual in HVAC Systems-Manual |
| 2 | A/C system noises can be generally categorized into 3 areas: Screeching, Squealing, Chirping noises Moaning noises Vibration/Rattle noises Start the engine. Ensure that the A/C is ON. Is a screeching, squealing noise heard when the A/C is engaged? | Go to Step 3 | Go to Step 9 |
| 3 | With the engine OFF, inspect the drive belt for excessive wear. Refer to Drive Belt Excessive Wear Diagnosis in Engine Mechanical-2.2L and Drive Belt Excessive Wear Diagnosis in Engine Mechanical-2.0L. Is the drive belt excessively worn? | Go to Step 18 | Go to Step 4 |
| 4 | Inspect the drive belt tension. Refer to Drive Belt Tensioner Diagnosis in Engine Mechanical-2.2L and Drive Belt Excessive Wear Diagnosis in Engine Mechanical-2.0L. Is the drive belt tension correct? | Go to Step 5 | Go to Step 19 |
| 5 | Inspect the drive belt for excessive oil coverage. Is the drive belt covered with oil? | Go to Step 17 | Go to Step 6 |
| 6 | Start the engine. Ensure that the A/C is ON. Inspect the compressor and the clutch. Is the A/C compressor locked up? | Go to Step 24 | Go to Step 7 |
| 7 | Is the A/C compressor clutch slipping? | Go to Step 23 | Go to Step 8 |
| 8 | CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Using a stethoscope, listen to the A/C compressor for any abnormal noises.Is the compressor causing an abnormal noise? | Go to Step 15 | Go to Step 10 |
| 9 | Does a moaning noise exist when the A/C clutch is engaged? | Go to Step 10 | Go to Step 12 |
| 10 | Listen to the A/C compressor components and mounting for noise concerns using a stethoscope. Are any of these components loose, damaged or excessively worn? | Go to Step 20 | Go to Step 11 |
| 11 | Idle the engine. Engage the A/C compressor clutch. Using a stethoscope, move around the entire refrigerant plumbing system. Listening for any abnormal noises caused by a component of the A/C system touching another component. Are any of the A/C components grounding out and causing a vibration noise? | Go to Step 22 | Go to Step 13 |
| 12 | Does a vibration or rattle noise exist when the A/C clutch is engaged? | Go to Step 13 | Go to Step 14 |
| 13 | Does the noise stop when the A/C clutch is disengaged? | Go to Step 15 | Go to Step 25 |
| 14 | Idle the engine in PARK with the A/C compressor clutch engaged. Using a stethoscope, move around the entire A/C system testing for any abnormal noises caused by a component. Do any of the A/C components cause an abnormal noise? | Go to Step 21 | Go to Step 25 |
| 15 | Verify that the A/C system is properly charged. Refer to Refrigerant System Capacities . Is the A/C system properly charged? | Go to Step 26 | Go to Step 16 |
| 16 | Recharge the A/C system to specification. Refer to Refrigerant Recovery and Recharging . Is the abnormal compressor noise still present? | Go to Step 24 | Go to Step 26 |
| 17 | Repair the oil leak. Refer to Oil Leak Diagnosis in Engine Mechanical-2.2L and Oil Leak Diagnosis in Engine Mechanical-2.0L. Is the repair complete? | Go to Step 26 | |
| 18 | Replace the drive belt. Refer to Drive Belt Replacement in Engine Mechanical-2.2L and Drive Belt Excessive Wear Diagnosis in Engine Mechanical-2.0L. Is the repair complete? | Go to Step 26 | |
| 19 | Replace the drive belt tensioner. Refer to Drive Belt Tensioner Replacement in Engine Mechanical-2.2L and Drive Belt Excessive Wear Diagnosis in Engine Mechanical-2.0L. Is the repair complete? | Go to Step 26 | |
| 20 | Repair or replace the A/C compressor mounting component. Is the repair complete? | Go to Step 26 | |
| 21 | Repair or replace the component which is causing the moaning concern as needed. Is the repair complete? | Go to Step 26 | |
| 22 | Correctly route or insulate the A/C component. Is the repair complete? | Go to Step 26 | |
| 23 | Replace the A/C compressor clutch. Refer to Compressor Clutch Assembly Replacement . Is the repair complete? | Go to Step 26 | |
| 24 | Replace the A/C compressor. Refer to Compressor Replacement (2.2L (L61)) or Compressor Replacement (2.0L (LSJ)) . Is the repair complete? | Go to Step 26 | |
| 25 | The concern may be caused by an engine related component. Refer to Vibration Analysis - Engine in Vibration Diagnosis and Correction. Did you find and correct the condition? | Go to Step 26 | |
| 26 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 |
| CAUTION |
|---|
| Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. |
Noise Diagnosis - Air Conditioning (A/C) System
Noise Diagnosis - HVAC Module
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Noise originating from the HVAC module. | |||
| 1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual in HVAC Systems-Manual |
| 2 | Start the engine. Cycle through all of the following: Blower motor speeds HVAC modes Temperature control settings Determine the type of noise: Scrape, pop Tick/click, chirp or groaning Air rush/whistle Is a scrape or pop noise evident when selecting modes or temperature settings? | Go to Step 6 | Go to Step 3 |
| 3 | Is a tick/click, chirping, groaning or scraping noise present, but decreases as blower motor speed is decreased? | Go to Step 6 | Go to Step 4 |
| 4 | Is an air rush/whistle noise evident in all modes but not all temperature settings? | Go to Step 6 | Go to Step 5 |
| 5 | Is an air rush/whistle noise evident only in defrost or floor mode? | Go to Step 6 | Go to Step 6 |
| 6 | Remove the I/P center trim panel. Refer to Trim Panel Replacement - Instrument Panel (I/P) Center in Instrument Panel, Gages and Console. Remove the center air outlet duct. Is the action complete? | Go to Step 7 | |
| 7 | Inspect the air flow doors for proper operation. Inspect the ducts for obstructions or foreign materials. Were any of these conditions found? | Go to Step 10 | Go to Step 8 |
| 8 | Inspect the mode and temperature doors and seals for warping or cracking. Are the doors in normal condition? | Go to Step 11 | Go to Step 9 |
| 9 | Replace the appropriate door and/or seals. Is the repair complete? | Go to Step 11 | |
| 10 | Remove any obstructions or foreign material found. Is the action complete? | Go to Step 11 | |
| 11 | Install the center air outlet duct. Install the I/P center trim panel. Refer to Trim Panel Replacement - Instrument Panel (I/P) Center in Instrument Panel, Gages and Console. Is the action complete? | Go to Step 12 | |
| 12 | Operate the system to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 |
Noise Diagnosis - HVAC Module
Odor Diagnosis
| Step | Action | Yes | No |
|---|---|---|---|
| DEFINITION: Odor originating or noticed through the HVAC system. | |||
| 1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual |
| 2 | Sit inside the vehicle. Close all of the doors and windows. Start the engine. Allow the engine to idle at normal operating temperature. Select the maximum blower speed. Select the PANEL air outlet mode. Select the coldest temperature setting. Cycle through all of the blower speeds, modes, and temperatures to define what type of odor is present. Musty smell Coolant smell Oil smell Does the odor have a musty smell? | Go to Step 3 | Go to Step 8 |
| 3 | Inspect the HVAC filter and the air inlet grille for debris. Is debris present? | Go to Step 4 | Go to Step 5 |
| 4 | Remove any debris. Is the action complete? | Go to Step 15 | |
| 5 | Inspect for wet carpeting. Is the carpet wet? | Go to Step 6 | Go to Step 8 |
| 6 | Inspect for the following conditions: Water leaks around the windshield Blockage of the HVAC module drain Leaks around the door seals Is a leak present? | Go to Step 7 | Go to Step 15 |
| 7 | Repair the leak as necessary. Is the repair complete? | Go to Step 15 | |
| 8 | Does the odor have a coolant smell? | Go to Step 9 | Go to Step 12 |
| 9 | Inspect the cooling system for leaks. Refer to Loss of Coolant in Engine Cooling. Is a leak present? | Go to Step 10 | Go to Step 12 |
| 10 | Inspect for coolant leaking inside the vehicle or for a film build-up on the windshield. Is the condition present? | Go to Step 11 | Go to Step 15 |
| 11 | Replace the heater core. Refer to Heater Core Replacement . Is the repair complete? | Go to Step 15 | |
| 12 | Does the odor have an oily smell? | Go to Step 13 | Go to Step 15 |
| 13 | Inspect the engine compartment for any leaks. Refer to the following procedures: Oil Leak Diagnosis in Engine Mechanical - 2.2L or Oil Leak Diagnosis in Engine Mechanical - 2.0L Fluid Leak Diagnosis in Automatic Transaxle - 4T40-E/4T45-E Repair any oil leaks. Is the repair complete? | Go to Step 15 | |
| 14 | A musty odor can be caused by mold or mildew build-up on the evaporator or the heater core or inside of the HVAC module. Refer to Odor Correction . Is the action complete? | Go to Step 15 | |
| 15 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2 |
Odor Diagnosis