GM Service Manual Online
For 1990-2009 cars only

Air Conditioning (A/C) System Performance Test Short Wheel Base

Table 1: A/C Performance Table with Aux A/C

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 air 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 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 127-152 mm (5-6 in).
  3. Select the following HVAC control settings:
  4. • The A/C ON.
    • The coldest temperature setting
    • The maximum blower speed
    • The I/P panel outlet mode
    • All I/P panel outlets are OPEN
    • Recirculation mode
  5. Install the temperature probes to the J 43600 in the left and right center A/C air outlets.
  6. Apply the parking brake.
  7. Place the transaxle/transmission in one of the following positions:
  8. • PARK for Automatic
    • NEUTRAL for Manual
  9. Start the engine.
  10. Operate the A/C system for 5 minutes.
  11. Inspect A/C components for the following conditions:
  12. •  Abnormal frost areas
    • Unusual noises

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

  13. Print the following information:
  14. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  15. Compare the low and high side pressures and the panel output temperatures 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 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 output temperature 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 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

or

Symptoms - HVAC Systems - Automatic

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


Object Number: 1747476  Size: MF

A/C Performance Table with Aux A/C

Ambient Air Temperature

Relative Humidity

Service Port Pressure

Maximum Discharge Air Temperature

Low Side

High Side

Left Front Center

Left Rear

13-18°C (55-65°F)

0-100%

151-220 kPa (22-32 psi)

537-937 kPa (78-136 psi)

5°C (41°F)

7°C (45°F)

19-24°C (66-75°F)

Below 40%

151-248 kPa (22-36 psi)

689-1109 kPa (100-161 psi)

8°C (46°F)

10°C (50°F)

Above 40%

151-282 kPa (22-41 psi)

757-1178 kPa (110-171 psi)

10°C (50°F)

12°C (54°F)

25-29°C (76-85°F)

Below 35%

186-289 kPa (27-42 psi)

978-1322 kPa (142-192 psi)

11°C (52°F)

13°C (55°F)

35-50%

206-303 kPa (30-44 psi)

1019-1336 kPa (148-194 psi)

12°C 54°F)

14°C (57°F)

Above 50%

213-323 kPa (31-47 psi)

1040-1378 kPa (151-200 psi)

14°C (57°F)

16°C (61°F)

30-35°C (86-95°F)

Below 30%

234-337 kPa (34-49 psi)

1212-1577 kPa (176-229 psi)

15°C (59°F)

18°C (64°F)

30-50%

248-351 kPa (36-51 psi)

1233-1598 kPa (179-232 psi)

17°C (63°F)

19°C (66°F)

Above 50%

261-372 kPa (38-54 psi)

1260-1619 kPa (183-235 psi)

19°C (66°F)

21°C (70°F)

36-41°C (96-105°F)

Below 20%

289-385 kPa (42-56 psi)

1488-1853 kPa (216-269 psi)

19°C (66°F)

21°C (70°F)

20-40%

296-399 kPa (43-58 psi)

1488-1853 kPa (216-269 psi)

21°C (70°F)

23°C (73°F)

Above 40%

310-413 kPa (45-60 psi)

1508-1853 kPa (219-269 psi)

22°C (72°F)

24°C (75°F)

42-46°C (106-115°F)

Below 20%

344-434 kPa (50-63 psi)

1770-2080 kPa (257-302 psi)

23°C (73°F)

25°C (77°F)

Above 20%

351-447 kPa (51-65 psi)

1770-2067 kPa (257-300 psi)

24°C (75°F)

27°C (81°F)

47-49°C (116-120°F)

Below 30%

392-482 kPa (57-70 psi)

1998-2301 kPa (290-334 psi)

27°C (81°F)

28°C (82°F)

Air Conditioning (A/C) System Performance Test Long Wheel Base - 1500 Series

Table 1: A/C Performance Table with Aux A/C

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 air 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 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 127-152 mm (5-6 in).
  3. Select the following HVAC control settings:
  4. • The A/C ON.
    • The coldest temperature setting
    • The maximum blower speed
    • The I/P panel outlet mode
    • All I/P panel outlets are OPEN
    • Recirculation mode
  5. Install the temperature probes to the J 43600 in the left and right center A/C air outlets.
  6. Apply the parking brake.
  7. Place the transaxle/transmission in one of the following positions:
  8. • PARK for Automatic
    • NEUTRAL for Manual
  9. Start the engine.
  10. Operate the A/C system for 5 minutes.
  11. Inspect A/C components for the following conditions:
  12. •  Abnormal frost areas
    • Unusual noises

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

  13. Print the following information:
  14. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  15. Compare the low and high side pressures and the panel output temperatures 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 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 output temperature 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 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

or

Symptoms - HVAC Systems - Automatic

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


Object Number: 1778260  Size: MF

A/C Performance Table with Aux A/C

Ambient Air Temperature

Relative Humidity

Service Port Pressure

Maximum Discharge Air Temperature

Low Side

High Side

Left Front Center

Left Rear

13-18°C (55-65°F)

0-100%

151-220 kPa (22-32 psi)

489-923 kPa (71-134 psi)

7°C (41°F)

10°C (45°F)

19-24°C (66-75°F)

Below 40%

151-234 kPa (22-34 psi)

578-1019 kPa (84-148 psi)

8°C (46°F)

12°C (52°F)

Above 40%

151-275 kPa (22-40 psi)

689-1129 kPa (100-164 psi)

10°C (50°F)

13°C (55°F)

25-29°C (76-85°F)

Below 35%

172-275 kPa (25-40 psi)

868-1219 kPa (126-177 psi)

10°C (50°F)

14°C (57°F)

35-50%

192-389 kPa (28-42 psi)

930-1336 kPa (148-194 psi)

12°C 54°F)

14°C (57°F)

Above 50%

206-310 kPa (30-45 psi)

971-1302 kPa (141-189 psi)

13°C (55°F)

18°C (63°F)

30-35°C (86-95°F)

Below 30%

220-323 kPa (32-47 psi)

1102-1460 kPa (160-212 psi)

14°C (57°F)

18°C (64°F)

30-50%

234-337 kPa (34-49 psi)

1129-1481 kPa (164-215 psi)

15°C (59°F)

19°C (66°F)

Above 50%

248-358 kPa (36-52 psi)

1157-1502 kPa (168-218 psi)

18°C (64°F)

20°C (68°F)

36-41°C (96-105°F)

Below 20%

275-378 kPa (40-55 psi)

1371-1722 kPa (199-250 psi)

18°C (64°F)

23°C (73°F)

20-40%

282-385 kPa (41-56 psi)

1378-1722 kPa (200-250 psi)

19°C (66°F)

23°C (73°F)

Above 40%

296-392 kPa (43-57 psi)

1391-1708 kPa (202-248 psi)

20°C (68°F)

24°C (75°F)

42-46°C (106-115°F)

Below 20%

330-420 kPa (48-61 psi)

1639-1942 kPa (238-282 psi)

22°C (70°F)

27°C (79°F)

Above 20%

337-427 kPa (49-62 psi)

1639-1922 kPa (238-279 psi)

23°C (72°F)

27°C (79°F)

47-49°C (116-120°F)

Below 30%

385-468 kPa (56-68 psi)

1860-2149 kPa (270-312 psi)

25°C (77°F)

28°C (82°F)

Air Conditioning (A/C) System Performance Test Long Wheel Base - 2500 Series

Table 1: A/C Performance Table with Aux A/C

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 air 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 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 127-152 mm (5-6 in).
  3. Select the following HVAC control settings:
  4. • The A/C ON.
    • The coldest temperature setting
    • The maximum blower speed
    • The I/P panel outlet mode
    • All I/P panel outlets are OPEN
    • Recirculation mode
  5. Install the temperature probes to the J 43600 in the left and right center A/C air outlets.
  6. Apply the parking brake.
  7. Place the transaxle/transmission in one of the following positions:
  8. • PARK for Automatic
    • NEUTRAL for Manual
  9. Start the engine.
  10. Operate the A/C system for 5 minutes.
  11. Inspect A/C components for the following conditions:
  12. •  Abnormal frost areas
    • Unusual noises

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

  13. Print the following information:
  14. • The panel outlet air temperatures
    • The low-side pressure
    • The high-side pressure
  15. Compare the low and high side pressures and the panel output temperatures 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 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 output temperature 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 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

or

Symptoms - HVAC Systems - Automatic

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


Object Number: 1782421  Size: MF

A/C Performance Table with Aux A/C

Ambient Air Temperature

Relative Humidity

Service Port Pressure

Maximum Discharge Air Temperature

Low Side

High Side

Left Front Center

Left Rear

13-18°C (55-65°F)

0-100%

151-268 kPa (22-39 psi)

819-1350 kPa (119-196 psi)

12°C (52°F)

15°C (59°F)

19-24°C (66-75°F)

Below 40%

172-310 kPa (25-45 psi)

999-1550 kPa (145-225 psi)

14°C (57°F)

17°C (61°F)

Above 40%

199-344 kPa (29-50 psi)

1123-1681 kPa (163-244 psi)

17°C (61°F)

19°C (66°F)

25-29°C (76-85°F)

Below 35%

248-358 kPa (36-52 psi)

1391-1832 kPa (202-266 psi)

18°C (63°F)

20°C (68°F)

35-50%

261-372 kPa (38-54 psi)

1460-1867 kPa (212-271 psi)

18°C 64°F)

22°C (70°F)

Above 50%

275-392 kPa (40-57 psi)

1508-1949 kPa (219-283 psi)

19°C (66°F)

23°C (72°F)

30-35°C (86-95°F)

Below 30%

303-420 kPa (44-61 psi)

1701-2177 kPa (247-316 psi)

22°C (70°F)

25°C (77°F)

30-50%

316-434 kPa (46-63 psi)

1743-2218 kPa (253-322 psi)

23°C (73°F)

25°C (77°F)

Above 50%

330-454 kPa (48-66 psi)

1791-2280 kPa (260-331 psi)

24°C (75°F)

27°C (79°F)

36-41°C (96-105°F)

Below 20%

365-482 kPa (53-70 psi)

2060-2528 kPa (299-367 psi)

25°C (77°F)

30°C (86°F)

20-40%

372-496 kPa (54-72 psi)

2080-2563 kPa (302-372 psi)

28°C (81°F)

30°C (86°F)

Above 40%

385-502 kPa (56-73 psi)

2122-2576 kPa (308-374 psi)

28°C (82°F)

30°C (86°F)

42-46°C (106-115°F)

Below 20%

440-544 kPa (64-79 psi)

2439-2838 kPa (354-412 psi)

29°C (84°F)

34°C (93°F)

Above 20%

440-551 kPa (64-80 psi)

2452-2852 kPa (356-414 psi)

30°C (86°F)

34°C (93°F)

47-49°C (116-120°F)

Below 30%

502-599 kPa (73-87 psi)

2762-3141 kPa (401-456 psi)

34°C (93°F)

41°C (105°F)