A/C Performance Test

WARNING: Refer to the applicable warnings and cautions for this system before performing the following operation. See Heating and Air Conditioning/Plumbing - Warning and Heating and Air Conditioning/Plumbing - Caution . Failure to follow these instructions may result in possible serious or fatal injury.

CAUTION: The use of an A/C recycling/charging station for purposes of determining the actual charge level of an A/C system is not recommend. Service recycling/charging stations do not reflect the correct amount of refrigerant charge in the A/C system after a single "reclaim" cycle. Tests have shown that it can take two or more "reclaim" cycles to remove all of the refrigerant charge, depending on the equipment being used. Use only the following procedure for determining the proper charge level.

NOTE: The A/C Cool Down test which can be initiated on the MTC or ATC system is not a valid test to determine A/C performance. It is intended to be only used at the assembly plant and should not be used at a dealer or repair facility. Use only the following procedure to check A/C performance.

Make sure the following conditions are met in the area where the test is to be performed:
- Maximum ambient temperature: 110°F (43.3°C)
- Minimum ambient temperature: 60°F (15.5°C)
- Minimum relative humidity: 20%
- Maximum relative humidity: 90%
Operate the heating-A/C system under the following conditions.
- Engine at normal operating temperature
- Engine at normal idle speed
- No sun-load in the cabin of the vehicle
- Vehicle doors and windows closed
- Transmission in Park
- A/C-heater controls set to Recirculation mode, full cool, panel mode, high blower and with A/C compressor engaged. If the A/C compressor does not engage, see the A/C SYSTEM DIAGNOSIS
- All panel outlet vanes open and positioned straight rearward
NOTE: If the following step is not performed, the results of this test will not be accurate.
Using a scan tool, operate the engine cooling fans at high speed from the totally integrated power module (TIPM) electronic control unit (ECU) view.
Insert a thermometer in the driver side center panel air outlet and operate the A/C system until the thermometer temperature stabilizes or a minimum of 5 minutes.
NOTE: This procedure requires you to know what the temperature and relative humidity is in your location at the time of the test. This information can be obtained from multiple sources, such as the internet or local news media.
With the A/C compressor clutch engaged, compare the observed panel outlet air temperature along with the ambient temperature of the work area and the relative humidity to the Maximum Panel Outlet Temperature chart.
If the air outlet temperature fails to meet the specifications in the Maximum Panel Outlet Temperature chart, refer to A/C SYSTEM DIAGNOSIS table.

A/C SYSTEM DIAGNOSIS

Condition	Possible Causes	Correction
Rapid A/C compressor clutch cycling (ten or more cycles per minute).	1. Low refrigerant system charge.	1. See REFRIGERANT SYSTEM LEAKS . Test the refrigerant system for leaks. Repair, evacuate and charge the refrigerant system, if required.
Equal pressures, but the compressor clutch does not engage.	1. No refrigerant in the refrigerant system.	1. See REFRIGERANT SYSTEM LEAKS . Test the refrigerant system for leaks. Repair, evacuate and charge the refrigerant system, if required.
-	2. Open fuse.	2. See SYSTEM WIRING DIAGRAMS for 300 or SYSTEM WIRING DIAGRAMS for Charger. Check the fuses in the Totally Integrated Power Module (TIPM) and the Rear Power Distribution Center (PDC). Repair the shorted circuit or component and replace the fuse(s), if required.
-	3. Inoperative A/C compressor clutch coil.	3. See A/C CLUTCH COIL . Test the compressor clutch coil and replace, if required.
-	4. Inoperative A/C compressor clutch relay.	4. See A/C CLUTCH COIL . Test the compressor clutch relay and relay circuits. Repair the circuits or replace the relay, if required.
-	5. Improperly installed or inoperative evaporator temperature sensor.	5. See SENSOR, Evaporator Temperature . Test the sensor and replace, if required.
-	6. Inoperative A/C pressure transducer.	6. See TRANSDUCER, A/C Pressure . Test the sensor and replace, if required.
-	7. Inoperative Powertrain Control Module (PCM) or Engine Control Module (ECM).	7. See GENERAL INFORMATION - SPECIAL TOOLS - DTC-BASED DIAGNOSTICS . Test the PCM/ECM and replace, if required.
Normal pressures, but A/C Performance Test air temperatures at center panel outlet are too high.	1. Excessive refrigerant oil in system.	1. See REFRIGERANT OIL CAPACITY . Recover the refrigerant from the refrigerant system and inspect the refrigerant oil content. Restore the refrigerant oil to the proper level, if required.
-	2. Blend door actuator (s) improperly installed or inoperative.	2. See ACTUATOR, Blend Door . Inspect the actuator(s) for proper operation and replace, if required.
-	3. Blend-air door(s) inoperative or sealing improperly.	3. See HOUSING, HVAC . Inspect the blend-air door(s) for proper operation and sealing. Repair if required.
The low side pressure is normal or slightly low, and the high side pressure is too low.	1. Low refrigerant system charge.	1. See REFRIGERANT SYSTEM LEAKS . Test the refrigerant system for leaks. Repair, evacuate and charge the refrigerant system, if required.
-	2. Refrigerant flow through the A/C evaporator is restricted.	2. See EVAPORATOR, A/C . Replace the restricted A/C evaporator, if required.
-	3. Inoperative A/C compressor.	3. See COMPRESSOR, A/C . Replace the A/C compressor, if required.
The low side pressure is normal or slightly high, and the high side pressure is too high.	1. A/C condenser air flow restricted.	1. See CONDENSER, A/C . Check the A/C condenser for damaged fins, foreign objects obstructing air flow through the condenser fins, and missing or improperly installed air seals. Clean, repair, or replace components as required.
-	2. Refrigerant flow through the A/C receiver/drier is restricted.	2. See DRIER, A/C Receiver . Replace the restricted A/C receiver/drier, if required.
-	3. Inoperative radiator cooling fan.	3. See COOLING . Test the radiator cooling fan and replace, if required.
-	4. Refrigerant system overcharged.	4. See REFRIGERANT SYSTEM CHARGE . Recover the refrigerant from the refrigerant system. Charge the refrigerant system to the proper level, if required.
-	5. Air in the refrigerant system.	5. See REFRIGERANT SYSTEM LEAKS . Test the refrigerant system for leaks. Repair, evacuate and charge the refrigerant system, if required.
-	6. Engine overheating.	6. See COOLING . Test the engine cooling system and repair, if required.
The low side pressure is too high, and the high side pressure is too low.	1. Accessory drive belt slipping.	1. See COOLING . Inspect the accessory drive belt condition and tension. Repair as required.
-	2. Inoperative A/C expansion valve.	2. See A/C EXPANSION VALVE . Replace the valve, if required.
-	3. Inoperative A/C compressor.	3. See COMPRESSOR, A/C . Replace the A/C compressor, if required.
The low side pressure is too low, and the high side pressure is too high.	1. Restricted refrigerant flow through the refrigerant lines.	1. See LINE, A/C Liquid , LINE, A/C Suction and LINE, A/C Discharge . Inspect the refrigerant lines for kinks, tight bends or improper routing. Correct the routing or replace the refrigerant line, if required.
-	2. Restricted refrigerant flow through the A/C expansion valve.	2. See A/C EXPANSION VALVE . Replace the valve, if required.
-	3. Restricted refrigerant flow through the A/C condenser.	3. See CONDENSER, A/C . Replace the restricted A/C condenser, if required.