Air Conditioning (A/C) System Performance Test. Cadillac STS 2008

For 1990-2009 cars only

Makes 🢒 Cadillac 🢒 2008 🢒 STS 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Air Conditioning (A/C) System Performance Test

Air Conditioning (A/C) System Performance Test LH2 w/ Standard Cooling

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.

This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

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

This step is to allow for vehicle variations as well as high ambient temperatures.

Step

Action

Values

Yes

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.

Park the vehicle inside or in the shade.
Open the windows in order to ventilate the interior of the vehicle.
If the A/C system was operating, allow the A/C system to equalize for about 5 minutes.
Turn OFF the ignition.
Install the J 43600 ACR 2000 Air Conditioning Service Center.
Record the ambient air temperature displayed on the J 43600 .
Record the low and high side STATIC pressure readings.

Are both the low side and high side pressures above 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

Important: Record the relative humidity and the ambient air temperature at the time of the test.

Close the vehicle doors and windows.
Open the driver door window 12.7-15.2 cm (5-6 inches).
Select the following HVAC control settings:

•	The A/C is ON

•	The maximum blower speed

•	The maximum blower speed selected on the auxiliary blower controls

•	Recirculation mode

•	The Face mode

•	The coldest temperature setting

•	Passenger setting is OFF

•	All A/C outlets are OPEN

Install the temperature probes of the J 43600 in the left and right center A/C air outlets.
Apply the parking brake.
Place the transaxle/transmission in the following position: PARK.
Start the engine.
Operate the A/C system for 5 minutes.
Inspect A/C components for the following conditions:

•	Abnormal frost areas

•	Unusual noises

Important: Make sure that the compressor is engaged when taking the data.

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

Print the following information:

•	The outlet air temperatures

•	The low-side pressure

•	The high-side pressure

Compare the low and high side pressures and the output temperatures 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 3

If the pressures and temperatures recorded do not fall within the specified ranges of the A/C Performance Table:

Continue to operate the A/C system for an additional 5 minutes.
RESET the J 43600 and record the pressures and temperatures again.
Compare the low and high side pressures and the output temperature to the A/C Performance Table.

Does all the data recorded fall within the specified ranges?

Go to Step 8

Go to Step 4

Do the high and low side pressures fall within the specified ranges, but the outlet temperatures do not?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 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

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

Is the high side pressure greater than or within the specified range, but the low side pressure is less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 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 Performance Table

Ambient Temperature	Relative Humidity	Low Side Service Port Pressure	High Side Service Port Pressure	Maximum Left Center Discharge Air Temperature	Maximum Left Side Rear Discharge Air Temperature
13-18°C (55-65°F)	0-100%	170-234 kPa (25-34 psi)	1101-1411 kPa (160-205 psi)	8°C (46°F)	11°C (52°F)
19-24°C (66-75°F)	Less than 40%	187-263 kPa (27-38 psi)	1241-1503 kPa (180-218 psi)	11°C (52°F)	14°C (57°F)
19-24°C (66-75°F)	Greater than 40%	194-271 kPa (28-39 psi)	1231-1551 kPa (179-225 psi)	12°C (54°F)	14°C (57°F)
25-29°C (76-85°F)	Less than 35%	218-286 kPa (32-42 psi)	1341-1591 kPa (194-231 psi)	13°C (55°F)	16°C (61°F)
	35-60%	193-276 kPa (28-40 psi)	1310-1551 kPa (190-225 psi)	14°C (57°F)	16°C (61°F)
	Greater than 60%	225-294 kPa (33-43 psi)	1393-1634 kPa (202-237 psi)	14°C (57°F)	17°C (63°F)
30-35°C (86-95°F)	Less than 30%	242-314 kPa (35-46 psi)	1471-1741 kPa (213-2531 psi)	16°C (61°F)	19°C (66°F)
	30-50%	245-317 kPa (36-46 psi)	1501-1761 kPa (218-255 psi)	17°C (63°F)	19°C (66°F)
	Greater than 50%	249-322 kPa (36-47 psi)	1531-1801 kPa (222-261 psi)	17°C (63°F)	20°C (68°F)
36-41°C (96-105°F)	Less than 20%	271-342 kPa (39-50 psi)	1631-1881 kPa (237-273 psi)	18°C (64°F)	21°C (70°F)
	20-40%	273-345 kPa (40-50 psi)	1593-1827 kPa (231-265 psi)	19°C (66°F)	22°C (72°F)
	Greater than 40%	276-359 kPa (40-52 psi)	1848-2041 kPa (268-296 psi)	20°C (68°F)	22°C (72°F)
42-46°C (106-115°F)	Less than 20%	301-367 kPa (44-53 psi)	1841-2048 kPa (267-297 psi)	20°C (68°F)	23°C (73°F)
42-46°C (106-115°F)	Greater than 20%	302-369 kPa (44-54 psi)	1801-2031 kPa (261-295 psi)	21°C (70°F)	24°C (75°F)
47-49°C (116-120°F)	Less than 30%	296-365 kPa (43-53 psi)	1868-2075 kPa (271-301 psi)	22°C (72°F)	25°C (77°F)

LH2 With Standard Cooling

Air Conditioning (A/C) System Performance Test LY7 w/Standard Cooling

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.

This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

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

This step is to allow for vehicle variations as well as high ambient temperatures.

Step

Action

Values

Yes

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.

Park the vehicle inside or in the shade.
Open the windows in order to ventilate the interior of the vehicle.
If the A/C system was operating, allow the A/C system to equalize for about 5 minutes.
Turn OFF the ignition.
Install the J 43600 ACR 2000 Air Conditioning Service Center.
Record the ambient air temperature displayed on the J 43600 .
Record the low and high side STATIC pressure readings.

Are both the low side and high side pressures above 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

Important: Record the relative humidity and the ambient air temperature at the time of the test.

Close the vehicle doors and windows.
Open the driver door window 12.7-15.2 cm (5-6 in).
Select the following HVAC control settings:

•	The A/C is ON.

•	The maximum blower speed

•	The maximum blower speed selected on the auxiliary blower controls

•	Recirculation mode

•	The Face mode

•	The coldest temperature setting

•	Passenger setting is OFF

•	All A/C outlets are OPEN.

Install the temperature probes of the J 43600 in the left and right center A/C air outlets.
Apply the parking brake.
Place the transaxle/transmission in the following position: PARK.
Start the engine.
Operate the A/C system for 5 minutes.
Inspect A/C components for the following conditions:

•	Abnormal frost areas

•	Unusual noises

Important: Make sure that the compressor is engaged when taking the data.

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

Print the following information:

•	The outlet air temperatures

•	The low-side pressure

•	The high-side pressure

Compare the low and high side pressures and the output temperatures 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 3

If the pressures and temperatures recorded do not fall within the specified ranges of the A/C Performance Table:

Continue to operate the A/C system for an additional 5 minutes.
RESET the J 43600 and record the pressures and temperatures again.
Compare the low and high side pressures and the output temperature to the A/C Performance Table.

Does all the data recorded fall within the specified ranges?

Go to Step 8

Go to Step 4

Do the high and low side pressures fall within the specified ranges, but the outlet temperatures do not?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 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

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

Is the high side pressure greater than or within the specified range, but the low side pressure is less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 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 Performance Table

Ambient Temperature	Relative Humidity	Low Side Service Port Pressure	High Side Service Port Pressure	Maximum Left Center Discharge Air Temperature	Maximum Left Side Rear Discharge Air Temperature
13-18°C (55-65°F)	0-100%	150-221 kPa (22-32 psi)	1191-1441 kPa (173-209 psi)	10°C (50°F)	11°C (52°F)
19-24°C (66-75°F)	Less than 40%	153-239 kPa (22-35 psi)	1303-1524 kPa (189-221 psi)	11°C (52°F)	13°C (55°F)
19-24°C (66-75°F)	Greater than 40%	169-257 kPa (25-37 psi)	1338-1558 kPa (184-226 psi)	12°C (54°F)	14°C (57°F)
25-29°C (76-85°F)	Less than 35%	187-261 kPa (27-38 psi)	1391-1591 kPa (202-231 psi)	13°C (55°F)	15°C (59°F)
	35-60%	196-262 kPa (28-38 psi)	1411-1634 kPa (205-237 psi)	14°C (57°F)	15°C (59°F)
	Greater than 60%	203-280 kPa (29-41 psi)	1517-1696 kPa (220-246 psi)	15°C (59°F)	16°C (61°F)
30-35°C (86-95°F)	Less than 30%	213-289 kPa (31-42 psi)	1511-1721 kPa (219-250 psi)	16°C (61°F)	18°C (64°F)
	30-50%	219-296 kPa (32-43 psi)	1511-1711 kPa (219-248 psi)	17°C (63°F)	18°C (64°F)
	Greater than 50%	227-307 kPa (33-45 psi)	1482-1682 kPa (215-244 psi)	18°C (64°F)	19°C (66°F)
36-41°C (96-105°F)	Less than 20%	242-316 kPa (35-46 psi)	1613-1820 kPa (234-264 psi)	18°C (64°F)	20°C (68°F)
	20-40%	245-322 kPa (36-47 psi)	1651-1841 kPa (239-267 psi)	19°C (66°F)	21°C (70°F)
	Greater than 40%	252-328 kPa (37-48 psi)	1631-1811 kPa (237-263 psi)	20°C (68°F)	21°C (70°F)
42-46°C (106-115°F)	Less than 20%	273-342 kPa (40-50 psi)	1801-1981 kPa (261-287 psi)	21°C (70°F)	23°C (73°F)
42-46°C (106-115°F)	Greater than 20%	276-346 kPa (40-50 psi)	1791-1941 kPa (260-282 psi)	21°C (70°F)	23°C (73°F)
47-49°C (116-120°F)	Less than 30%	302-359 kPa (44-52 psi)	2075-2186 kPa (301-317 psi)	22°C (72°F)	25°C (75°F)

LY7 With Standard Cooling

Air Conditioning (A/C) System Performance Test LH2 w/ Heavy Duty Cooling

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.

This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

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

This step is to allow for vehicle variations as well as high ambient temperatures.

Step

Action

Values

Yes

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.

Park the vehicle inside or in the shade.
Open the windows in order to ventilate the interior of the vehicle.
If the A/C system was operating, allow the A/C system to equalize for about 5 minutes.
Turn OFF the ignition.
Install the J 43600 ACR 2000 Air Conditioning Service Center.
Record the ambient air temperature displayed on the J 43600 .
Record the low and high side STATIC pressure readings.

Are both the low side and high side pressures above 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

Important: Record the relative humidity and the ambient air temperature at the time of the test.

Close the vehicle doors and windows.
Open the driver door window 12.7-15.2 cm (5-6 inches).
Select the following HVAC control settings:

•	The A/C is ON

•	The maximum blower speed

•	The maximum blower speed selected on the auxiliary blower controls

•	Recirculation mode

•	The Face mode

•	The coldest temperature setting

•	Passenger setting is OFF

•	All A/C outlets are OPEN

Install the temperature probes of the J 43600 in the left and right center A/C air outlets.
Apply the parking brake.
Place the transaxle/transmission in the following position: PARK.
Start the engine.
Operate the A/C system for 5 minutes.
Inspect A/C components for the following conditions:

•	Abnormal frost areas

•	Unusual noises

Important: Make sure that the compressor is engaged when taking the data.

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

Print the following information:

•	The outlet air temperatures

•	The low-side pressure

•	The high-side pressure

Compare the low and high side pressures and the output temperatures 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 3

If the pressures and temperatures recorded do not fall within the specified ranges of the A/C Performance Table:

Continue to operate the A/C system for an additional 5 minutes.
RESET the J 43600 and record the pressures and temperatures again.
Compare the low and high side pressures and the output temperature to the A/C Performance Table.

Does all the data recorded fall within the specified ranges?

Go to Step 8

Go to Step 4

Do the high and low side pressures fall within the specified ranges, but the outlet temperatures do not?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 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

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

Is the high side pressure greater than or within the specified range, but the low side pressure is less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 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 Performance Table

Ambient Temperature	Relative Humidity	Low Side Service Port Pressure	High Side Service Port Pressure	Maximum Left Center Discharge Air Temperature	Maximum Left Side Rear Discharge Air Temperature
13-18°C (55-65°F)	0-100%	164-231 kPa (24-34 psi)	1338-1565 kPa (194-227 psi)	10°C (50°F)	11°C (52°F)
19-24°C (66-75°F)	Less than 40%	191-272 kPa (28-39 psi)	1524-1675 kPa (221-243 psi)	12°C (54°F)	13°C (55°F)
19-24°C (66-75°F)	Greater than 40%	195-288 kPa (28-42 psi)	1411-1691 kPa (205-245 psi)	13°C (55°F)	15°C (59°F)
25-29°C (76-85°F)	Less than 35%	222-300 kPa (32-44 psi)	1524-1731 kPa (221-251 psi)	15°C (59°F)	16°C (61°F)
	35-60%	230-310 kPa (33-45 psi)	1561-1781 kPa (226-258 psi)	15°C (59°F)	17°C (63°F)
	Greater than 60%	236-328 kPa (34-49 psi)	1581-1821 kPa (229-264 psi)	16°C (61°F)	18°C (64°F)
30-35°C (86-95°F)	Less than 30%	248-332 kPa (36-48 psi)	1661-1868 kPa (241-271 psi)	17°C (63°F)	19°C (66°F)
	30-50%	257-349 kPa (37-51 psi)	1681-1924 kPa (244-279 psi)	18°C (64°F)	20°C (68°F)
	Greater than 50%	270-375 kPa (39-54 psi)	1701-1981 kPa (247-287 psi)	20°C (68°F)	22°C (72°F)
36-41°C (96-105°F)	Less than 20%	275-355 kPa (40-52 psi)	1811-2051 kPa (263-298 psi)	19°C (66°F)	21°C (70°F)
	20-40%	283-378 kPa (41-55 psi)	1821-2081 kPa (264-302 psi)	21°C (70°F)	22°C (72°F)
	Greater than 40%	301-400 kPa (44-58 psi)	1917-2137 kPa (278-310 psi)	22°C (72°F)	24°C (75°F)
42-46°C (106-115°F)	Less than 20%	304-382 kPa (44-55 psi)	2006-2193 kPa (291-318 psi)	22°C (72°F)	23°C (73°F)
42-46°C (106-115°F)	Greater than 20%	315-414 kPa (46-60 psi)	2027-2261 kPa (294-328 psi)	23°C (73°F)	25°C (77°F)
47-49°C (116-120°F)	Less than 30%	331-413 kPa (51-62 psi)	2091-2272 kPa (303-329 psi)	24°C (75°F)	26°C (79°F)

LH2 With Heavy Duty Cooling

Air Conditioning (A/C) System Performance Test LY7 w/ Heavy Duty Cooling

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.

This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

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

This step is to allow for vehicle variations as well as high ambient temperatures.

Step

Action

Values

Yes

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.

Park the vehicle inside or in the shade.
Open the windows in order to ventilate the interior of the vehicle.
If the A/C system was operating, allow the A/C system to equalize for about 5 minutes.
Turn OFF the ignition.
Install the J 43600 ACR 2000 Air Conditioning Service Center.
Record the ambient air temperature displayed on the J 43600 .
Record the low and high side STATIC pressure readings.

Are both the low side and high side pressures above 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

Important: Record the relative humidity and the ambient air temperature at the time of the test.

Close the vehicle doors and windows.
Open the driver door window 12.7-15.2 cm (5-6 inches).
Select the following HVAC control settings:

•	The A/C is ON

•	The maximum blower speed

•	The maximum blower speed selected on the auxiliary blower controls

•	Recirculation mode

•	The Face mode

•	The coldest temperature setting

•	Passenger setting is OFF

•	All A/C outlets are OPEN

Install the temperature probes of the J 43600 in the left and right center A/C air outlets.
Apply the parking brake.
Place the transaxle/transmission in the following position: PARK.
Start the engine.
Operate the A/C system for 5 minutes.
Inspect A/C components for the following conditions:

•	Abnormal frost areas

•	Unusual noises

Important: Make sure that the compressor is engaged when taking the data.

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

Print the following information:

•	The outlet air temperatures

•	The low-side pressure

•	The high-side pressure

Compare the low and high side pressures and the output temperatures 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 3

If the pressures and temperatures recorded do not fall within the specified ranges of the A/C Performance Table:

Continue to operate the A/C system for an additional 5 minutes.
RESET the J 43600 and record the pressures and temperatures again.
Compare the low and high side pressures and the output temperature to the A/C Performance Table.

Does all the data recorded fall within the specified ranges?

Go to Step 8

Go to Step 4

Do the high and low side pressures fall within the specified ranges, but the outlet temperatures do not?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 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

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

Is the high side pressure greater than or within the specified range, but the low side pressure is less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 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 Performance Table

Ambient Temperature	Relative Humidity	Low Side Service Port Pressure	High Side Service Port Pressure	Maximum Left Center Discharge Air Temperature	Maximum Left Side Rear Discharge Air Temperature
13-18°C (55-65°F)	0-100%	153-221 kPa (22-30 psi)	861-1121 kPa (125-163 psi)	11°C (52°F)	12°C (54°F)
19-24°C (66-75°F)	Less than 40%	180-262 kPa (26-38 psi)	1069-1291 kPa (155-187 psi)	14°C (57°F)	15°C (59°F)
19-24°C (66-75°F)	Greater than 40%	185-274 kPa (27-40 psi)	1048-1311 kPa (152-190 psi)	14°C (57°F)	15°C (59°F)
25-29°C (76-85°F)	Less than 35%	215-292 kPa (31-42 psi)	1201-1441 kPa (174-209 psi)	16°C (61°F)	17°C (63°F)
	35-60%	221-298 kPa (32-43 psi)	1248-1475 kPa (181-214 psi)	16°C (61°F)	18°C (64°F)
	Greater than 60%	225-311 kPa (33-45 psi)	1262-1510 kPa (183-219 psi)	17°C (63°F)	19°C (66°F)
30-35°C (86-95°F)	Less than 30%	244-326 kPa (35-47 psi)	1386-1648 kPa (201-239 psi)	18°C (646°F)	20°C (68°F)
	30-50%	250-338 kPa (36-49 psi)	1361-1662 kPa (197-241 psi)	19°C (66°F)	21°C (70°F)
	Greater than 50%	258-354 kPa (37-51 psi)	1371-1682 kPa (199-244 psi)	20°C (68°F)	22°C (72°F)
36-41°C (96-105°F)	Less than 20%	275-356 kPa (40-52 psi)	1541-1758 kPa (224-264 psi)	20°C (68°F)	23°C (73°F)
	20-40%	281-370 kPa (41-54 psi)	1551-1821 kPa (225-264 psi)	22°C (72°F)	24°C (75°F)
	Greater than 40%	292-384 kPa (42-56 psi)	1551-1831 kPa (225-266 psi)	23°C (73°F)	25°C (77°F)
42-46°C (106-115°F)	Less than 20%	309-385 kPa (45-56 psi)	1731-1971 kPa (251-286 psi)	23°C (73°F)	25°C (77°F)
42-46°C (106-115°F)	Greater than 20%	316-401 kPa (46-58 psi)	1741-1981 kPa (253-287 psi)	24°C (75°F)	27°C (81°F)
47-49°C (116-120°F)	Less than 30%	345-411 kPa (50-61 psi)	1965-2193 kPa (285-318 psi)	25°C (77°F)	28°C (82°F)

LY7 With Heavy Duty Cooling

Air Conditioning (A/C) System Performance Test LC3

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.

This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.

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

This step is to allow for vehicle variations as well as high ambient temperatures.

Step

Action

Values

Yes

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.

Park the vehicle inside or in the shade.
Open the windows in order to ventilate the interior of the vehicle.
If the A/C system was operating, allow the A/C system to equalize for about 5 minutes.
Turn OFF the ignition.
Install the J 43600 ACR 2000 Air Conditioning Service Center.
Record the ambient air temperature displayed on the J 43600 .
Record the low and high side STATIC pressure readings.

Are both the low side and high side pressures above 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

Important: Record the relative humidity and the ambient air temperature at the time of the test.

Close the vehicle doors and windows.
Open the driver door window 12.7-15.2 cm (5-6 inches).
Select the following HVAC control settings:

•	The A/C is ON

•	The maximum blower speed

•	The maximum blower speed selected on the auxiliary blower controls

•	Recirculation mode

•	The Face mode

•	The coldest temperature setting

•	Passenger setting is OFF

•	All A/C outlets are OPEN

Install the temperature probes of the J 43600 in the left and right center A/C air outlets.
Apply the parking brake.
Place the transaxle/transmission in the following position: PARK.
Start the engine.
Operate the A/C system for 5 minutes.
Inspect A/C components for the following conditions:

•	Abnormal frost areas

•	Unusual noises

Important: Make sure that the compressor is engaged when taking the data.

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

Print the following information:

•	The outlet air temperatures

•	The low-side pressure

•	The high-side pressure

Compare the low and high side pressures and the output temperatures 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 3

If the pressures and temperatures recorded do not fall within the specified ranges of the A/C Performance Table:

Continue to operate the A/C system for an additional 5 minutes.
RESET the J 43600 and record the pressures and temperatures again.
Compare the low and high side pressures and the output temperature to the A/C Performance Table.

Does all the data recorded fall within the specified ranges?

Go to Step 8

Go to Step 4

Do the high and low side pressures fall within the specified ranges, but the outlet temperatures do not?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone A

Go to Step 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

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

Is the high side pressure greater than or within the specified range, but the low side pressure is less than the specified range?

Go to Air Conditioning (A/C) Diagnostics - Pressure Zone D

Go to Step 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 Performance Table

Ambient Temperature	Relative Humidity	Low Side Service Port Pressure	High Side Service Port Pressure	Maximum Left Center Discharge Air Temperature	Maximum Left Side Rear Discharge Air Temperature
13-18°C (55-65°F)	0-100%	172-241 kPa (25-35 psi)	1570-1791 kPa (228-260 psi)	8°C (46°F)	10°C (50°F)
19-24°C (66-75°F)	Less than 40%	199-289 kPa (29-42 psi)	1818-2101 kPa (264-305 psi)	13°C (54°F)	15°C (59°F)
19-24°C (66-75°F)	Greater than 40%	206-296 kPa (30-43 psi)	1770-2067 kPa (257-300 psi)	13°C (54°F)	15°C (59°F)
25-29°C (76-85°F)	Less than 35%	241-323 kPa (35-47 psi)	2053-2308 kPa (298-335 psi)	14°C (57°F)	18°C (64°F)
	35-60%	248-323 kPa (36-47 psi)	2032-2308 kPa (295-335 psi)	15°C (59°F)	18°C (64°F)
	Greater than 60%	248-337 kPa (36-49 psi)	2011-2301 kPa (292-334 psi)	17°C (61°F)	19°C (663°F)
30-35°C (86-95°F)	Less than 30%	275-358 kPa (40-52 psi)	2239-2549 kPa (325-370 psi)	18°C (64°F)	22°C (70°F)
	30-50%	275-372 kPa (40-54 psi)	2232-2563 kPa (324-372 psi)	18°C (64°F)	23°C (73°F)
	Greater than 50%	289-385 kPa (42-56 psi)	2232-2569 kPa (324-373 psi)	20°C (68°F)	23°C (73°F)
36-41°C (96-105°F)	Less than 20%	310-392 kPa (45-57 psi)	2466-2790 kPa (358-405 psi)	20°C (68°F)	23°C (73°F)
	20-40%	316-406 kPa (46-59 psi)	2466-2811 kPa (358-408 psi)	22°C (70°F)	25°C (77°F)
	Greater than 40%	323-420 kPa (47-61 psi)	2480-2831 kPa (360-411 psi)	23°C (72°F)	27°C (79°F)
42-46°C (106-115°F)	Less than 20%	344-427 kPa (50-62 psi)	2700-2983 kPa (392-433 psi)	23°C (72°F)	27°C (79°F)
42-46°C (106-115°F)	Greater than 20%	351-440 kPa (51-64 psi)	2707-3010 kPa (393-437 psi)	24°C (75°F)	28°C (82°F)
47-49°C (116-120°F)	Less than 30%	385-468 kPa (56-68 psi)	2900-3196 kPa (421-464 psi)	27°C (79°F)	29°C (84°F)

LC3