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For 1990-2009 cars only

Air Conditioning (A/C) System Performance Test w/ C69

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

  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:
  3. • Without Scan Tool
       - Turn ON the ignition.
       - Simultaneously press the A/C and RECIRC switches on the HVAC control module.
    • With Scan Tool
       - Turn ON the ignition.
       - Use the Instant OAT Update procedure in the scan tool Special Functions.
  4. Open the windows in order to ventilate the interior of the vehicle.
  5. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
  6. Turn OFF the ignition.
  7. Install the J 43600 .
  8. Record the ambient air temperature displayed on the J 43600 .
  9. 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
  5. Install the temperature probes of the J 43600 in the left and right center panel air outlets.
  6. Apply the parking brake.
  7. Place the transaxle/transmission in PARK.
  8. Start the engine.
  9. Operate the A/C system for 5 minutes.
  10. Inspect A/C components for the following conditions:
  11. • Abnormal frost areas
    • Unusual noises

    Important: Press the RESET button, before using the print function of the J 43600 .

  12. Print the following information:
  13. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  14. 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 - Automatic

A/C System Pressure - Zone Classification with Aux A/C


Object Number: 1831960  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

Maximum Left Rear Discharge Air Temperature

13-18°C (55-65°F)

0-100%

172-275 kPa (25-40 psi)

1419-1770 kPa (206-257 psi)

12°C (52°F)

13°C (55°F)

19-24°C (66-75°F)

Below 40%

192-289 kPa (28-42 psi)

1564-1812 kPa (227-263 psi)

13°C (55°F)

15°C (59°F)

Above 40%

199-296 kPa (29-43 psi)

1419-1694 kPa (206-246 psi)

15°C (59°F)

18°C (63°F)

25-29°C (76-85°F)

Below 35%

206-303 kPa (30-44 psi)

1564-1812 kPa (227-263 psi)

17°C (61°F)

18°C (64°F)

35-60%

241-337 kPa (35-49 psi)

1591-1915 kPa (231-278 psi)

18°C (63°F)

19°C (66°F)

Above 60%

248-344 kPa (36-50 psi)

1632-1922 kPa (237-279 psi)

18°C (63°F)

20°C (68°F)

30-35°C (86-95°F)

Below 30%

268-372 kPa (39-54 psi)

1839-2156 kPa (267-313 psi)

19°C (66°F)

23°C (72°F)

30-50%

196-399 kPa (43-58 psi)

1674-1949 kPa (243-283 psi)

20°C (68°F)

23°C (73°F)

Above 50%

275-385 kPa (40-56 psi)

1722-2060 kPa (250-299 psi)

23°C (72°F)

25°C (77°F)

36-41°C (96-105°F)

Below 20%

289-378 kPa (42-55 psi)

1750-1956 kPa (254-284 psi)

23°C (72°F)

25°C (77°F)

20-40%

296-399 kPa (43-58 psi)

1880-2777 kPa (273-316 psi)

23°C (73°F)

27°C (79°F)

Above 40%

323-427 kPa (47-62 psi)

1956-2204 kPa (284-320 psi)

24°C (75°F)

28°C (82°F)

42-46°C (106-115°F)

Below 20%

358-461 kPa (52-67 psi)

2177-2411 kPa (316-350 psi)

25°C (77°F)

29°C (84°F)

Above 20%

351-454 kPa (51-66 psi)

2163-2404 kPa (314-349 psi)

27°C (79°F)

30°C (86°F)

47-49°C (116-120°F)

Below 30%

399-502 kPa (58-73 psi)

2439-2645 kPa (354-384 psi)

29°C (84°F)

32°C (88°F)

Air Conditioning (A/C) System Performance Test w/o C69

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

  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:
  3. • Without Scan Tool
       - Turn ON the ignition.
       - Simultaneously press the A/C and RECIRC switches on the HVAC control module.
    • With Scan Tool
       - Turn ON the ignition.
       - Use the Instant OAT Update procedure in the scan tool Special Functions.
  4. Open the windows in order to ventilate the interior of the vehicle.
  5. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes.
  6. Turn OFF the ignition.
  7. Install the J 43600 ACR 2000 Air Conditioning Service Center.
  8. Record the ambient air temperature displayed on the J 43600 .
  9. 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
  5. Install the temperature probes of the J 43600 in the left and right center panel air outlets.
  6. Apply the parking brake.
  7. Place the transaxle/transmission in PARK.
  8. Start the engine.
  9. Operate the A/C system for 5 minutes.
  10. Inspect A/C components for the following conditions:
  11. • Abnormal frost areas
    • Unusual noises

    Important: Press the RESET button, before using the print function of the J 43600 .

  12. Print the following information:
  13. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  14. 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 - Automatic

A/C System Pressure - Zone Classification


Object Number: 1831961  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%

130-296 kPa (19-43 psi)

876-1412 kPa (127-205 psi)

8°C (46°F)

19-24°C (66-75°F)

Below 40%

144-303 kPa (21-44 psi)

1129-1639 kPa (164-238 psi)

12°C (52°F)

Above 40%

151-303 kPa (22-44 psi)

1205-1688 kPa (175-245 psi)

03°C (50°F)

25-29°C (76-85°F)

Below 35%

151-303 kPa (22-44 psi)

1334-1846 kPa (198-268 psi)

13°C (54°F)

35-60%

179-282 kPa (26-41 psi)

1646-1922 kPa (239-279 psi)

13°C (54°F)

Above 50%

179-282 kPa (26-41 psi)

1667-1908 kPa (242-277 psi)

12°C (52°F)

30-35°C (86-95°F)

Below 30%

179-268 kPa (26-39 psi)

1446-1701 kPa (210-247 psi)

14°C (57°F)

30-50%

179-282 kPa (26-41 psi)

1481-1694 kPa (215-246 psi)

14°C (57°F)

Above 50%

179-275 kPa (26-40psi)

1416-1653 kPa (206-240 psi)

13°C (55°F)

36-41°C (96-105°F)

Below 20%

213-310 kPa (31-45 psi)

1660-1887 kPa (241-274 psi)

15°C (59°F)

20-40%

213-310 kPa (31-45 psi)

1653-1908 kPa (240-277 psi)

15°C (59°F)

Above 40%

206-310 kPa (30-45 psi)

1626-1853 kPa (236-269 psi)

15°C (59°F)

42-46°C (106-115°F)

Below 20%

234-337 kPa (34-49 psi)

1825-2053 kPa (265-298 psi)

18°C (63°F)

Above 20%

241-344 kPa (35-50 psi)

1798-2046 kPa (261-297 psi)

18°C (63°F)

47-49°C (116-120°F)

Below 30%

254-351 kPa (37-51 psi)

2004-2246 kPa (291-326 psi)

18°C (64°F)