Step
| Action
| Value(s)
| Yes
| No
|
|
Important:
| • | The vehicle must be parked inside or in the shade. The ambient
temperature must be at least 16°C (60°F). |
| • | Do not induce additional air flow across the front of vehicle
during the test. |
| • | If you were sent here from a DTC diagnostic table, clear the DTC
upon completion of this test. |
|
DEFINITION: This test measures the A/C system
operating efficiency by comparing:
| • | The ambient air temperature |
| • | Low side refrigerant pressure |
| • | High side refrigerant pressure |
| • | Passenger compartment discharge air temperature |
|
1
|
- Turn OFF the ignition.
- Engage the parking brake.
- Allow the A/C system to equalize (This will take about 2 minutes).
- Open the windows in order to ventilate the interior.
- Open the hood and install a J 39500-B
.
- Record the high and the low side static pressures.
- Record the ambient temperature.
Are both the high and the low side pressures within 103 kPa (15 psi)
of the ambient temperature?
| --
| Go to
Step 2
| Go to
Step 3
|
2
|
- Vent the engine exhaust, if necessary.
- Close all the doors and the windows, but leave the driver's side
window open 13 cm (5 in).
- Set the A/C control to the following:
| • | Passenger control in the neutral position |
- Open the A/C air outlet deflectors.
- Install a J 6742-03
.
- Place the transmission shift lever in PARK.
- Start the engine and maintain idle.
- Record the ambient temperature.
- Record the relative humidity. Use a psychrometer or consult the
local weather bureau.
- Run the A/C system until the outlet air reaches a stabilized temperature
(about 5 minutes).
- Inspect the system for any abnormal frost areas.
- Listen for any unusual noises.
- Record the following data:
| • | Center outlet air temperatures |
- Compare the readings with the data in the table below.
Does all of the data recorded fall within the specified ranges of the
table below?
| --
| Go to
Step 5
| Go to
Step 3
|
3
|
- Continue to perform the A/C system test for an additional 5 minutes.
- Turn OFF the ignition.
- Record the pressures and temperatures.
- Compare the readings with the table below.
Does all of the data recorded fall within the specified ranges of the
table below?
| --
| Go to
Step 5
| Go to
VDOT Air Conditioning (A/C) System Diagnosis
|
4
|
- Perform a leak test. Refer to
Leak Testing
.
- Recover the refrigerant from the A/C system. Refer to
Refrigerant Recovery and Recharging
.
- Repair the leak as necessary and recharge.
Did you complete the repair?
| --
| Go to
Step 5
| --
|
5
| Operate the system in order to verify the repair.
Did you correct the condition?
| --
| System OK
| Go to
Symptoms
|
Ambient Temperature
| Relative
Humidity
| Low Side Service Port Pressure
| High Side Service Port Pressure
| Maximum Left Center Discharge
Air Temperature
|
16°C (60°F)
| 0-100 %
| 228-269 kPa
(33-39 psi)
| 1000-1207 kPa (145-175 psi)
| 11°C (52°F)
|
21°C (70°F)
| Below 40 %
| 228-269 kPa (33-39 psi)
| 869-1076 kPa (126-156 psi)
| 11°C
(52°F)
|
Above 40 %
| 241-283 kPa (34-41 psi)
| 890-1096 kPa (129-159 psi)
| 12°C
(56°F)
|
27°C (80°F)
| Below 40 %
| 276-317 kPa (40-46 psi)
| 1048-1255 kPa
(152-182 psi)
| 16°C (60°F)
|
Above 40 %
| 290-331 kPa (42-48 psi)
| 1069-1276 kPa
(155-185 psi)
| 16°C (60°F)
|
32°C (90°F)
| Below 40 %
| 324-365 kPa
(47-53 psi)
| 1283-1496 kPa (186-217 psi)
| 19°C (67°F)
|
Above 40 %
| 352-393 kPa
(51-57 psi)
| 1310-1517 kPa (190-220 psi)
| 21°C (70°F)
|
38°C (100°F)
| Below 40 %
| 345-386 kPa (50-56 psi)
| 1427-1703 kPa (207-247 psi)
| 19°C
(67°F)
|
Above 40 %
| 372-414 kPa (54-60 psi)
| 1455-1731 kPa (211-251 psi)
| 21°C
(70°F)
|
43°C (110°F)
| Below 40 %
| 372-414 kPa (54-60 psi)
| 1572-1848 kPa
(228-268 psi)
| 22°C (71°F)
|
Above 40 %
| 421-462 kPa (61-67 psi)
| 1655-1931 kPa
(240-280 psi)
| 24°C (75°F)
|
49°C (120°F)
| Below 40 %
| 462-503 kPa (67-73 psi)
| 1820-2096 kPa
(264-304 psi)
| 26°C (79°F)
|
