Operating After Filling Refrigerant Circuit
Only start engine after refrigerant circuit has been assembled.
If possible start engine only with a filled refrigerant circuit.
Do not start the engine while evacuating the refrigerant circuit or when the circuit is already evacuated (the A/C compressor could be damaged). Refer to REFRIGERANT CIRCUIT, GENERAL PRECAUTIONS (A/C System with Refrigerant R134a; Refrigerant Circuit, Using Service Station).
Compressor is always driven by the pulley or by the driveshaft (there is no magnetic clutch). To prevent damage when the compressor is idling, it is lubricated by an "internal oil circuit".
The compressor has an "internal oil circuit" to ensure the compressor is not damaged when refrigerant circuit is empty. Prerequisite for the internal lubrication is residual refrigerant oil in compressor.
The engine may only be started when the refrigerant circuit is installed correctly. If for example the refrigerant lines are not connected to the compressor and the engine is started then the compressor may be destroyed by the build-up of internal heat.
The A/C Compressor Regulator Valve -N280- is not activated when the refrigerant circuit is empty and the compressor idles with the engine. As there is no refrigerant in the circuit the oil required to lubricate is not fed to the compressor.
- All removed parts are in again.
- The refrigerant circuit is filled. Refer to REFRIGERANT CIRCUIT (A/C System with Refrigerant R134a; Refrigerant Circuit, Using Service Station).
If it is necessary to start the engine with a discharged refrigerant circuit:
- Refrigerant circuit must fully assembled.
- There must be no vacuum in the refrigerant circuit.
- At least a quarter of the specified refrigerant oil must be in the compressor.
- Do not let the engine RPM go above 2, 500.
- The engine should only run as long as absolutely necessary.
Note the following when starting engine for first time after filling refrigerant circuit:
-- Follow the information about starting the A/C system after installing the compressor. Refer to A/C Compressor -G111- (A/C System with Refrigerant R134a; A/C System, General Information).
-- Start engine with the compressor turned off ("ECON" mode set, the indicator lamp in the ECON button turns on and the indicator lamp in the AC button does not turn on) and wait until the engine idle speed has stabilized.
-- Open all instrument panel vents.
-- Set the temperature preset on the Climatronic Control Module -J255- A/C control head to "cold" (for the driver and passenger side).
-- Press the ECON button or the AC button to turn on the compressor ("Auto" mode selected and the indicator lamp in the ECON button does not turn on and the lamp in the AC button turns on) let the A/C compressor run for at least five minutes with the engine in idle.