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Makes 🢒 Chevrolet 🢒 2008 🢒 Equinox 🢒 HVAC 🢒 Heating, Ventilation, and Air Conditioning 🢒 Air Conditioning (A/C) System Performance Test

Air Conditioning (A/C) System Performance Test LY7

Table 1: A/C Performance Table

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

Test Description

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 ambient temperatures.

Step

Action

Values

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. Update the ambient air temperature display. Refer to Ambient Air Temperature Display Updating.
  3. Open the windows in order to ventilate the interior of the vehicle.
  4. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
  5. Turn OFF the ignition.
  6. Install the J 43600 .
  7. Record the ambient air temperature displayed on the J 43600 .
  8. Record the low and high side STATIC pressure readings.

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

More than 16°C (60°F) - 345 kPa (50 psi)

More than 24°C (75°F) - 483 kPa (70 psi)

More than 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 drivers door window 12.7-15.2 cm (5-6 in).
  3. Select the following HVAC control settings:
    4. • The A/C is ON
    • The coldest temperature setting
    • The maximum blower speed
    • Recirculation mode
    • The panel outlet mode
    • All panel 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 transaxle/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: Press the RESET button, before using the print function of the J 43600 .

  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. RESET the J 43600 and 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 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


Object Number: 1974496 Size: MF

A/C Performance Table

Ambient Temperature

Relative Humidity

Low Side Service Port Pressure

High Side Service Port Pressure

Maximum Left Center Discharge Air Temperature

13-18°C (55-65°F)

0-100%

151-254 kPa (22-37 psi)

1033-1412 kPa (150-205 psi)

9°C (48°F)

19-24°C (66-75°F)

Below 40%

151-234 kPa (22-34 psi)

1150-1550 kPa (167-225 psi)

8°C (46°F)

Above 40%

165-275 kPa (24-40 psi)

1233-1557 kPa (179-226 psi)

12°C (52°F)

25-29°C (76-85°F)

Below 35%

165-254 kPa (24-37 psi)

1240-1619 kPa (180-235 psi)

10°C (50°F)

35-50%

186-261 kPa (27-38 psi)

1391-1722 kPa (202-250 psi)

12°C (52°F)

Above 50%

206-289 kPa (30-42 psi)

1419-1736 kPa (206-252 psi)

13°C (55°F)

30-35°C (86-95°F)

Below 30%

199-282 kPa (29-41 psi)

1508-1791 kPa (219-260 psi)

13°C (55°F)

30-50%

206-289 kPa (30-42 psi)

1502-1812 kPa (218-263 psi)

14°C (57°F)

Above 50%

227-303 kPa (33-44 psi)

1515-1839 kPa (220-267 psi)

15°C (59°F)

36-41°C (96-105°F)

Below 20%

234-316 kPa (34-46 psi)

1688-1970 kPa (245-286 psi)

17°C (61°F)

20-40%

241-316 kPa (35-46 psi)

1701-1977 kPa (247-287 psi)

18°C (63°F)

Above 40%

248-316 kPa (36-46 psi)

1722-1977 kPa (250-287 psi)

18°C (63°F)

42-46°C (106-115°F)

Below 20%

275-351 kPa (40-51 psi)

1887-2129 kPa (274-309 psi)

19°C (66°F)

Above 20%

275-337 kPa (40-49 psi)

1887-2122 kPa (274-308 psi)

19°C (66°F)

47-49°C (116-120°F)

Below 30%

310-392 kPa (45-57 psi)

2053-2335 kPa (298-339 psi)

22°C (70°F)

Air Conditioning (A/C) System Performance Test LNJ

Table 1: A/C Performance Table

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

Test Description

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 ambient temperatures.

Step

Action

Values

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. Update the ambient air temperature display. Refer to Ambient Air Temperature Display Updating.
  3. Open the windows in order to ventilate the interior of the vehicle.
  4. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
  5. Turn OFF the ignition.
  6. Install the J 43600 .
  7. Record the ambient air temperature displayed on the J 43600 .
  8. Record the low and high side STATIC pressure readings.

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

More than 16°C (60°F) - 345 kPa (50 psi)

More than 24°C (75°F) - 483 kPa (70 psi)

More than 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 drivers door window 12.7-15.2 cm (5-6 in).
  3. Select the following HVAC control settings:
    4. • The A/C is ON
    • The coldest temperature setting
    • The maximum blower speed
    • Recirculation mode
    • The panel outlet mode
    • All panel 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 transaxle/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: Press the RESET button, before using the print function of the J 43600 .

  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. RESET the J 43600 and 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 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


Object Number: 1974554 Size: MF

A/C Performance Table

Ambient Temperature

Relative Humidity

Low Side Service Port Pressure

High Side Service Port Pressure

Maximum Left Center Discharge Air Temperature

13-18°C (55-65°F)

0-100%

117-192 kPa (17-28 psi)

971-1322 kPa (141-192 psi)

8°C (46°F)

19-24°C (66-75°F)

Below 40%

158-227 kPa (23-33 psi)

1019-1322 kPa (148-192 psi)

9°C (48°F)

Above 40%

137-261 kPa (20-38 psi)

999-1412 kPa (145-205 psi)

13°C (54°F)

25-29°C (76-85°F)

Below 35%

186-254 kPa (27-37 psi)

1178-1433 kPa (171-208 psi)

13°C (54°F)

35-50%

179-261 kPa (26-38 psi)

1240-1557 kPa (180-226 psi)

13°C (55°F)

Above 50%

186-275 kPa (27-40 psi)

1260-1529 kPa (183-222 psi)

15°C (59°F)

30-35°C (86-95°F)

Below 30%

192-282 kPa (28-41 psi)

1302-1653 kPa (189-240 psi)

14°C (57°F)

30-50%

213-303 kPa (31-44 psi)

1336-1715 kPa (194-249 psi)

17°C (61°F)

Above 50%

220-323 kPa (32-47 psi)

1378-1763 kPa (200-256 psi)

19°C (66°F)

36-41°C (96-105°F)

Below 20%

227-303 kPa (33-44 psi)

1412-1688 kPa (205-245 psi)

18°C (63°F)

20-40%

234-323 kPa (34-47 psi)

1460-1729 kPa (212-251 psi)

19°C (66°F)

Above 40%

254-351 kPa (37-51 psi)

1488-1770 kPa (216-257 psi)

22°C (70°F)

42-46°C (106-115°F)

Below 20%

254-323 kPa (37-47 psi)

1570-1812 kPa (228-263 psi)

19°C (66°F)

Above 20%

261-358 kPa (38-52 psi)

1612-1853 kPa (234-269 psi)

22°C (70°F)

47-49°C (116-120°F)

Below 30%

275-365 kPa (40-53 psi)

1729-1998 kPa (251-290 psi)

23°C (73°F)