GM Service Manual Online
For 1990-2009 cars only
Table 1: A/C Performance Table
Table 2: A/C Performance Table - with Rear A/C

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 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. 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 the low and high side STATIC pressure readings.

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

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

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

Greater 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. • A/C setting
    • Recirculation mode
    • Maximum blower speed
    • Panel mode
    • Coldest temperature setting
    • Open all panel air outlets
    • If equipped, maximum auxiliary blower speed
    • If equipped, coldest auxiliary temperature setting
    • If equipped, open all auxiliary air outlets
  5. Install the temperature probes of J 43600 in the left and right center panel air outlets.
  6. Apply the parking brake.
  7. Place the transaxle in PARK.
  8. Start the engine.
  9. Operate the A/C system for 5 minutes.
  10. Inspect the A/C components for abnormal frost areas and for unusual noises.
  11. Important: Press the RESET button, before using the print function of J 43600 .

  12. Print the following information:
  13. • The panel outlet air temperature
    • The low-side pressure
    • The high-side pressure
  14. Compare the printed information to the table below.

Does all the data recorded fall within the specified ranges of the table below?

--

Go to Step 8

Go to Step 3

3

If the pressures and temperature recorded do not fall within the specified ranges, perform the following procedure:

  1. Continue to operate the A/C system for an additional 5 minutes.
  2. RESET J 43600 and record the pressures and temperature again.
  3. Compare the new results to the table below.

Does all the data recorded fall within the specified ranges of the table below?

--

Go to Step 8

Go to Step 4

4

Do the pressures fall within the specified ranges, but the panel outlet temperature does 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


Object Number: 1542861  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%

151-213 kPa (22-31 psi)

792-1212 kPa (115-176 psi)

12°C (52°F)

19-24°C (66-75°F)

Below 40%

151-220 kPa (22-32 psi)

847-1267 kPa (123-184 psi)

12°C (52°F)

Above 40%

151-275 kPa (22-40 psi)

971-1398 kPa (141-203 psi)

15°C (59°F)

25-29°C (76-85°F)

Below 35%

151-261 kPa (22-38 psi)

1102-1502 kPa (160-218 psi)

14°C (57°F)

35-50%

179-282 kPa (26-41 psi)

1171-1550 kPa (170-225 psi)

17°C (61°F)

Above 50%

192-316 kPa (28-46 psi)

1219-1557 kPa (177-226 psi)

19°C (66°F)

30-35°C (86-95°F)

Below 30%

192-310 kPa (28-45 psi)

1302-1646 kPa (189-239 psi)

18°C (64°F)

30-50%

213-337 kPa (31-49 psi)

1336-1688 kPa (194-245 psi)

20°C (68°F)

Above 50%

241-372 kPa (35-54 psi)

1398-1750 kPa (203-254 psi)

23°C (73°F)

36-41°C (96-105°F)

Below 20%

248-351 kPa (36-51 psi)

1522-1860 kPa (221-270 psi)

23°C (72°F)

20-40%

254-378 kPa (37-55 psi)

1543-1880 kPa (224-273 psi)

23°C (73°F)

Above 40%

282-399 kPa (41-58 psi)

1591-1908 kPa (231-277 psi)

25°C (77°F)

42-46°C (106-115°F)

Below 20%

303-399 kPa (44-58 psi)

1756-2053 kPa (255-298 psi)

25°C (77°F)

Above 20%

310-420 kPa (45-61 psi)

1777-2060 kPa (258-299 psi)

28°C (81°F)

47-49°C (116-120°F)

Below 30%

358-454 kPa (52-66 psi)

1970-2239 kPa (286-325 psi)

30°C (86°F)


Object Number: 1542835  Size: MF

A/C Performance Table - with Rear A/C

Ambient Air Temperature

Relative Humidity

Service Port Pressure

Maximum Left Center A/C Discharge Air Temperature

Maximum Left/Top Rear A/C Discharge Air Temperature

Low Side

High Side

13-18°C (55-65°F)

0-100%

151-289 kPa (22-42 psi)

730-1212 kPa (106-176 psi)

10°C (50°F)

13°C (54°F)

19-24°C (66-75°F)

Below 40%

151-248 kPa (22-36 psi)

709-1171 kPa (103-170 psi)

10°C (50°F)

13°C (55°F)

Above 40%

172-316 kPa (25-46 psi)

757-1336 kPa (110-194 psi)

13°C (55°F)

17°C (61°F)

25-29°C (76-85°F)

Below 35%

165-275 kPa (24-40 psi)

978-1332 kPa (142-192 psi)

13°C (54°F)

15°C (59°F)

35-60%

199-296 kPa (29-43 psi)

1067-1357 kPa (155-197 psi)

13°C (55°F)

17°C (61°F)

Above 60%

227-337 kPa (33-49 psi)

1129-1446 kPa (164-210 psi)

15°C (59°F)

18°C (64°F)

30-35°C (86-95°F)

Below 30%

206-303 kPa (30-44 psi)

1178-1653 kPa (171-240 psi)

14°C (57°F)

18°C (64°F)

30-50%

227-323 kPa (33-47 psi)

1233-1688 kPa (179-245 psi)

15°C (59°F)

20°C (68°F)

Above 50%

254-358 kPa (37-52 psi)

1281-1722 kPa (186-250 psi)

18°C (63°F)

23°C (72°F)

36-41°C (96-105°F)

Below 20%

227-337 kPa (33-49 psi)

1419-1743 kPa (206-253 psi)

17°C (61°F)

20°C (68°F)

20-40%

254-351 kPa (37-51 psi)

1205-1729 kPa (175-251 psi)

18°C (63°F)

23°C (72°F)

Above 40%

275-378 kPa (40-55 psi)

1446-1722 kPa (210-250 psi)

18°C (64°F)

24°C (75°F)

42-46°C (106-115°F)

Below 20%

289-372 kPa (42-54 psi)

1619-1929 kPa (235-280 psi)

18°C (64°F)

23°C (73°F)

Above 20%

296-378 kPa (43-55 psi)

1619-1901 kPa (235-276 psi)

19°C (66°F)

25°C (77°F)

47-49°C (116-120°F)

Below 30%

330-413 kPa (48-60 psi)

1853-2239 kPa (269-325 psi)

25°C (76°F)

28°C (82°F)