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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Monte Carlo 🢒 HVAC 🢒 Heating, Ventilation, and Air Conditioning 🢒 Air Conditioning (A/C) System Performance Test

Air Conditioning (A/C) System Performance Test LZE, LZ4, LGD

Table 1: A/C Performance Table

Test Description

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

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

    2.

  2. This step measures the performance of the A/C system.

    3.

  3. This step is to allow for vehicle variations as well as high ambient air temperatures.

Step

Action

Value(s)

Yes

No

Important: 

   • The ambient air temperature must be at least 16°C (60°F).
   • Do not induce additional air flow across the front of the vehicle during the test.
   • If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.

1

  1. Park the vehicle inside or in the shade.
  2. Open the windows in order to ventilate the interior of the vehicle.
  3. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
  4. Turn OFF the ignition
  5. Install the J 43600 ACR 2000 Air Conditioning Service Center.
  6. Record the ambient air temperature displayed on the J 43600 .
  7. Record readings of the low and high side STATIC pressures.

Are both the low and high side pressures within the specified value?

Above 16°C (60°F) - 345 kPa (50 psi)

Above 24°C (75°F) - 483 kPa (70 psi)

Above 33°C (90°F) - 690 kPa (100 psi)

Go to Step 2

Go to Leak Testing

2

    Important: Record the relative humidity and the ambient air temperature AT THE TIME OF THE TEST.

  1. Close the vehicle doors and windows.
  2. Open the driver door window 12.7-15.2 cm (5-6 in).
  3. Select the following HVAC control setting:
    4. • The A/C is ON
    • The coldest temperature setting
    • The maximum blower speed
    • Recirculation mode
    • The IP panel outlet mode
    • All IP panel outlets are OPEN
    • The passenger side of a Dual Zone HVAC control module is turned OFF
  4. Install the temperature probes of the J 43600 in the left and right center panel air outlets.
  5. Apply the parking brake.
  6. Place the transmission in PARK
  7. Start the engine.
  8. Operate the A/C system for 5 minutes.
  9. Inspect A/C components for the following conditions:
    10. •  Abnormal frost areas
    • Unusual noises

    Important: When performing this step it is necessary to press the RESET button on the J 43600 before pressing the PRINT button.

  10. Print the following information:
    11. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  11. Compare the low and high side pressures and the panel output temperatures to the A/C performance table below.

Does all the data recorded fall within the specified ranges of the A/C performance table?

--

Go to Step 8

Go to Step 3

3

If the pressures and temperatures recorded do not fall within the specified ranges:

  1. Continue to operate the A/C system for an additional 5 minutes.
  2. Record the pressures and temperatures again.
  3. Compare the low and high side pressures and the panel output temperature to the A/C performance table.

Does all the data recorded fall within the specified ranges of the A/C performance table?

--

Go to Step 8

Go to Step 4

4

Do the high and low side pressures fall within the specified ranges, but the panel outlet temperatures do not?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 5

5

Is the low side pressure greater than the specified range, but the high side pressure is within or less than the specified range?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone B

Go to Step 6

6

Are the low and high side pressures both greater than the specified ranges?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone C

Go to Step 7

7

Is the high side pressure greater than the specified range, but the low side pressure is within or less than the specified range?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 8

8

Operate the system in order to verify the test results.

Did you find the same results?

--

System OK

Go to Symptoms - HVAC Systems - Manual

A/C System Pressure - Zone Classification
Object Number: 1684900 Size: MF

A/C Performance Table

Ambient Air Temperature

Relative Humidity

Service Port Pressure

Maximum Left Center Discharge Air Temperature

Low Side

High Side

13-18°C (55-65°F)

0-100%

151-199 kPa (22-29 psi)

888-1157 kPa (129-168 psi)

6°C (43°F)

19-24°C (66-75°F)

Below 40%

151-192 kPa (22-28 psi)

1026-1481 kPa (149-215 psi)

6°C (43°F)

Above 40%

151-234 kPa (22-34 psi)

1047-1446 kPa (152-210 psi)

7°C (46°F)

25-29°C (76-85°F)

Below 35%

151-220 kPa (22-32 psi)

1233-1515 kPa (179-220 psi)

8°C (48°F)

35-50%

151-227 kPa (22-33 psi)

1233-1550 kPa (179-225 psi)

10°C (50°F)

Above 50%

165-254 kPa (24-37 psi)

1233-1460 kPa (179-212 psi)

13°C (55°F)

30-35°C (86-95°F)

Below 30%

165-248 kPa (24-36 psi)

1391-1660 kPa (202-241 psi)

13°C (55°F)

30-50%

172-261 kPa (25-38 psi)

1391-1639 kPa (202-238 psi)

18°C (65°F)

Above 50%

192-275 kPa (28-40 psi)

1378-1619 kPa (200-235 psi)

19°C (66°F)

36-41°C (96-105°F)

Below 20%

192-275 kPa (28-40 psi)

1591-1860 kPa (231-270 psi)

17°C (64°F)

20-40%

199-289 kPa (29-42 psi)

1591-1839 kPa (231-267 psi)

19°C (66°F)

Above 40%

213-296 kPa (31-43 psi)

1570-1860 kPa (228-270 psi)

21°C (70°F)

42-46°C (106-115°F)

Below 20%

234-310 kPa (34-45 psi)

1791-2018 kPa (260-293 psi)

17°C (64°F)

Above 20%

234-330 kPa (34-48 psi)

1777-2101 kPa (258-305 psi)

23°C (73°F)

47-49°C (116-120°F)

Below 30%

268-337 kPa (39-49 psi)

1942-2308 kPa (282-335 psi)

23°C (73°F)

Air Conditioning (A/C) System Performance Test LS4

Table 1: A/C Performance Table

Test Description

This test measures the operating efficiency of the A/C system under the following conditions:

    • The current ambient air temperature (AAT)
    • 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

The numbers below refer to the step numbers on the diagnostic table.

  1. This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

    2.

  2. This step measures the performance of the A/C system.

    3.

  3. This step is to allow for vehicle variations as well as high (AATs).

Step

Action

Values

Yes

No

Important: 

   • The ambient air temperature (AAT) must be at least 16°C (60°F).
   • Do not induce additional air flow across the front of the vehicle during the test.
   • If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.

1

  1. Park the vehicle inside or in the shade.
  2. Open the windows in order to ventilate the interior of the vehicle.
  3. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
  4. Turn OFF the ignition.
  5. Install the J 43600 ACR 2000 Air Conditioning Service Center.
  6. Record the ambient air temperature (AAT) displayed on the J 43600 .
  7. Record readings of the low and high side STATIC pressures.

Are both the low and high side pressures within the specified value?

Above 16°C (60°F) - 345 kPa (50 psi)

Above 24°C (75°F) - 483 kPa (70 psi)

Above 33°C (90°F) - 690 kPa (100 psi)

Go to Step 2

Go to Leak Testing

2

    Important: Record the relative humidity and the AAT AT THE TIME OF THE TEST.

  1. Close the vehicle doors and windows.
  2. Open the driver door window 12.7-15.2 cm (5-6 in).
  3. Select the following HVAC control setting:
    4. • The A/C is ON.
    • The coldest temperature setting
    • The maximum blower speed
    • Recirculation mode
    • The instrument panel (I/P) outlet mode
    • All I/P outlets are OPEN
  4. Install the temperature probes of the J 43600 in the left and right center panel air outlets.
  5. Apply the parking brake.
  6. Place the transmission in PARK.
  7. Start the engine.
  8. Operate the A/C system for 5 minutes.
  9. Inspect A/C components for the following conditions:
    10. •  Abnormal frost areas
    • Unusual noises

    Important: When performing this step it is necessary to press the RESET button on the J 43600 before pressing the PRINT button.

  10. Print the following information:
    11. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  11. Compare the low and high side pressures and the panel output temperatures to the A/C performance table below.

Does all the data recorded fall within the specified ranges of the A/C performance table?

--

Go to Step 8

Go to Step 3

3

If the pressures and temperatures recorded do not fall within the specified ranges:

  1. Continue to operate the A/C system for an additional 5 minutes.
  2. Record the pressures and temperatures again.
  3. Compare the low and high side pressures and the panel output temperature to the A/C performance table.

Does all the data recorded fall within the specified ranges of the A/C performance table?

--

Go to Step 8

Go to Step 4

4

Do the high and low side pressures fall within the specified ranges, but the panel outlet temperatures do not?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 5

5

Is the low side pressure greater than the specified range, but the high side pressure is within or less than the specified range?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone B

Go to Step 6

6

Are the low and high side pressures both greater than the specified ranges?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone C

Go to Step 7

7

Is the high side pressure greater than the specified range, but the low side pressure is within or less than the specified range?

--

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 8

8

Operate the system in order to verify the test results.

Did you find the same results?

--

System OK

Go to Symptoms - HVAC Systems - Manual

A/C System Pressure - Zone Classification
Object Number: 1602588 Size: MF

A/C Performance Table

Ambient Air Temperature

Relative Humidity

Service Port Pressure

Maximum Left Center Discharge Air Temperature

Low Side

High Side

13-18°C (55-65°F)

0-100%

151-234 kPa (22-34 psi)

558-909 kPa (81-132 psi)

12°C (52°F)

19-24°C (66-75°F)

Below 40%

151-234 kPa (22-34 psi)

730-1109 kPa (106-161 psi)

9°C (48°F)

Above 40%

151-275 kPa (22-40 psi)

771-1150 kPa (112-167 psi)

14°C (57°F)

25-29°C (76-85°F)

Below 35%

165-268 kPa (24-39 psi)

1012-1322 kPa (147-192 psi)

13°C (54°F)

35-50%

186-282 kPa (27-41 psi)

1019-1329 kPa (148-193 psi)

13°C (55°F)

Above 50%

206-310 kPa (30-45 psi)

1040-1336 kPa (151-194 psi)

17°C (61°F)

30-35°C (86-95°F)

Below 30%

206-303 kPa (30-44 psi)

1233-1577 kPa (179-229 psi)

15°C (59°F)

30-50%

220-323 kPa (32-47 psi)

1240-1577 kPa (180-229 psi)

18°C (63°F)

Above 50%

241-344 kPa (35-50 psi)

1247-1577 kPa (181-229 psi)

19°C (66°F)

36-41°C (96-105°F)

Below 20%

248-344 kPa (36-50 psi)

1502-1839 kPa (218-267 psi)

18°C (64°F)

20-40%

254-358 kPa (37-52 psi)

1502-1839 kPa (218-267 psi)

19°C (66°F)

Above 40%

275-372 kPa (40-54 psi)

1502-1832 kPa (218-266 psi)

22°C (70°F)

42-46°C (106-115°F)

Below 20%

296-385 kPa (43-56 psi)

1770-2060 kPa (257-299 psi)

22°C (70°F)

Above 20%

303-392 kPa (44-57 psi)

1756-2053 kPa (255-298 psi)

23°C (72°F)

47-49°C (116-120°F)

Below 30%

344-427 kPa (50-62 psi)

1977-2280 kPa (287-331 psi)

25°C (77°F)