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

Air Conditioning (A/C) System Performance Test 4.4L

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 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 allows 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.
   • Allow the vehicle to adjust to ambient temperature.
   • The outside air temperature sensor must be updated prior to performing the A/C Performance Test to allow the engine control module (ECM) to update to the current ambient temperature.

1

  1. To activate the outside air temperature (OAT) sensor instant update feature, refer to Control Module References for Scan Tool Information or perform the following procedure:
    2. 1.1. Put the ignition to the ON position.
    1.2. Press the following 3 buttons simultaneously:
       • Fan Up
       • Front Defrost
       • Rear Defog
  2. Park the vehicle inside or in the shade.
  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 ACR 2000 Air Conditioning Service Center.
  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?

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. Install the temperature probes of the J 43600 in the left and right center panel air outlets.
  4. Apply the parking brake.
  5. Place the transaxle in PARK.
  6. Start the engine.
  7. Select the following HVAC control settings:
    8. • A/C setting
    • Recirculation mode
    • Maximum blower speed
    • Panel mode
    • Coldest temperature setting
    • All panel outlets are Open
  8. Using the scan tool, command the engine cooling fan to 50 percent for ambient temperatures below 32.2°C (90°F) and 90 percent for ambient temperatures above 32.2°C (90°F).
  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 .

  11. Print the following information:
    12. • The panel outlet air temperature
    • The low-side pressure
    • The high-side pressure
  12. Compare the low and high side pressures and the panel 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 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 temperature again.
  3. Compare the low and high side pressures and the panel 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 temperature 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: 1688568 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)

1440-1729 kPa (209-251 psi)

10°C (50°F)

19-24°C (66-75°F)

Below 40%

151-227 kPa (22-33 psi)

1488-1777 kPa (216-258 psi)

10°C (50°F)

Above 40%

151-268 kPa (22-39 psi)

1557-1970 kPa (226-286 psi)

14°C (57°F)

25-29°C (76-85°F)

Below 35%

165-254 kPa (24-37 psi)

1632-1929 kPa (237-280 psi)

14°C (57°F)

35-50%

186-268 kPa (27-39 psi)

1681-1915 kPa (244-278 psi)

15°C (59°F)

Above 50%

199-303 kPa (29-44 psi)

1481-2018 kPa (215-293 psi)

18°C (64°F)

30-35°C (86-95°F)

Below 30%

192-282 kPa (28-41 psi)

1481-1998 kPa (215-290 psi)

15°C (59°F)

30-50%

206-310 kPa (30-45 psi)

1550-2067 kPa (225-300 psi)

18°C (64°F)

Above 50%

227-351 kPa (33-51 psi)

1515-2177 kPa (220-316 psi)

20°C (68°F)

36-41°C (96-105°F)

Below 20%

220-303 kPa (32-44 psi)

1688-2087 kPa (245-303 psi)

17°C (63°F)

20-40%

234-330 kPa (34-48 psi)

1880-2149 kPa (273-312 psi)

19°C (66°F)

Above 40%

254-365 kPa (37-53 psi)

1949-2308 kPa (283-335 psi)

21°C (70°F)

42-46°C (106-115°F)

Below 20%

248-330 kPa (36-48 psi)

1846-2197 kPa (268-319 psi)

19°C (66°F)

Above 20%

261-365 kPa (38-53 psi)

2011-2170 kPa (292-315 psi)

22°C (72°F)

47-49°C (116-120°F)

Below 30%

289-378 kPa (42-55 psi)

2122-2342 kPa (308-340 psi)

23°C (73°F)

Air Conditioning (A/C) System Performance Test 4.6L

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 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.
   • Allow the vehicle to adjust to ambient temperature.
   • The outside air temperature sensor must be updated prior to performing the A/C Performance Test to allow the engine control module (ECM) to update to the current ambient temperature.

1

  1. To activate the outside air temperature (OAT) sensor instant update feature, refer to Control Module References for Scan Tool Information or perform the following procedure:
    2. 1.1. Put the ignition to the ON position.
    1.2. Press the following 3 buttons simultaneously:
       • Fan Up
       • Front Defrost
       • Rear Defog
  2. Park the vehicle inside or in the shade.
  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 ACR 2000 Air Conditioning Service Center.
  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?

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. Install the temperature probes of the J 43600 in the left and right center panel air outlets.
  4. Apply the parking brake.
  5. Place the transaxle in PARK.
  6. Start the engine.
  7. Select the following HVAC control settings:
    8. • A/C setting
    • Recirculation mode
    • Maximum blower speed
    • Panel mode
    • Coldest temperature setting
    • All panel outlets are Open
  8. Using the scan tool, command the engine cooling fan to 50 percent for ambient temperatures below 32.2°C (90°F) and 90 percent for ambient temperatures above 32.2°C (90°F).
  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 .

  11. Print the following information:
    12. • The panel outlet air temperature
    • The low-side pressure
    • The high-side pressure
  12. Compare the low and high side pressures and the panel 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 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 temperature again.
  3. Compare the low and high side pressures and the panel 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 temperature 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: 1511739 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%

150-194 kPa (22-28 psi)

1250-1570 kPa (181-228 psi)

8°C (46°F)

18-24°C (65-75°F)

Below 40%

150-230 kPa (22-33 psi)

1430-1780 kPa (208-258 psi)

10°C (50°F)

Above 40%

153-259 kPa (23-38 psi)

1460-2000 kPa (212-290 psi)

13°C (55°F)

24-29°C (75-85°F)

Below 35%

172-256 kPa (25-37 psi)

1570-1940 kPa (228-282 psi)

12°C (54°F)

35-60%

187-273 kPa (27-40 psi)

1670-2080 kPa (242-302 psi)

14°C (57°F)

Above 60%

198-306 kPa (29-44 psi)

1750-2360 kPa (254-343 psi)

17°C (63°F)

29-35°C (85-95°F)

Below 30%

194-284 kPa (28-41 psi)

1670-2090 kPa (242-303 psi)

14°C (57°F)

30-50%

211-315 kPa (31-46 psi)

1810-2370 kPa (263-344 psi)

18°C (64°F)

Above 50%

233-362 kPa (34-53 psi)

2000-2790 kPa (290-405 psi)

22°C (72°F)

35-41°C (95-105°F)

Below 20%

213-297 kPa (31-43 psi)

1730-2100 kPa (251-305 psi)

15°C (59°F)

20-40%

228-337 kPa (33-49 psi)

1870-2470 kPa (271-358 psi)

19°C (66°F)

Above 40%

259-377 kPa (38-55 psi)

2150-2840 kPa (312-412 psi)

23°C (73°F)

41-46°C (105-115°F)

Below 20%

236-320 kPa (34-46 psi)

1830-2220 kPa (266-322 psi)

17°C (63°F)

Above 20%

257-368 kPa (37-53 psi)

2020-2670 kPa (293-388 psi)

22°C (72°F)

46-49°C (115-120°F)

Below 30%

280-361 kPa (41-52 psi)

2140-2550 kPa (311-370 psi)

21°C (70°F)