A/C Compressor, Removing And Installing: Installing
-- If the A/C compressor is replaced, check the ribbed belt for damage and if necessary replace. Refer to RIBBED BELT, REMOVING AND INSTALLING .
Install in reverse order of removal. Pay attention to the following for the procedure:
-- Initiate the "A/C compressor first start" function in Guided Fault Finding.
-- Clean the surfaces on the A/C compressor and bracket.
-- Insert the alignment bushings -1- in the A/C compressor -2-.
Incorrectly installed alignment sleeves and dirty or damaged contact surfaces can cause alignment irregularities between the A/C compressor and engine. Alignment irregularities damage the A/C compressor over time.
If the A/C compressor is replaced due to certain complaints (for example, internal damage), clean the refrigerant circuit. Refer to A/C System - with Refrigerant R134a.
There is an unspecified amount of refrigerant oil in the removed A/C compressor, so therefore pay attention to the information on replacing the A/C compressor. Refer to A/C System with Refrigerant R134a.
Risk of damaging the A/C compressor. Refrigerant oil may accumulate in the compression chamber of the removed A/C compressor.
- After installing a new A/C compressor or filling with fresh refrigerant oil, turn the A/C compressor 10 times by hand before installing the ribbed belt.
Pay Attention to the Following When Starting the Engine for the First Time After Filling the Refrigerant Circuit:
-- Follow the information on operating the A/C system after installing the A/C compressor. Refer to A/C System with Refrigerant R134a.
-- Start the engine with the A/C compressor already turned off (indicator lamp button A/C is off) and wait until the idle RPM stabilizes.
-- Open the instrument panel vents.
-- Select for example the temperature preset "Lo" on the Heater and A/C Controls -EX21-.
-- Switch on the A/C compressor (indicator lamp in the A/C button turns on) and let the engine idle for at least 5 minutes.
The A/C compressor is driven by the ribbed belt pulley (there is no solenoid coupling).
If the A/C compressor is blocked, the compressor shaft overload protection is activated. The blockage is mostly recognized by deformations/bumps on the ribbed belt pulley. In addition, the blockage can be recognized by the abraded rubber in the area of the ribbed belt pulley.
The A/C compressor is equipped with a protected oil supply, this prevents A/C compressor damage in the event that the system is empty. This means that approximately 40 to 50 cm3 of refrigerant oil remains in the A/C compressor.
Only start the engine when the refrigerant circuit is filled.
Only start the engine if the refrigerant circuit was correctly installed. If, for example, the refrigerant lines are not connected to the A/C compressor and the engine is started and runs, then the A/C compressor may be destroyed by the build-up of internal heat.
A/C Compressor Regulator Valve -N280- is not activated when the refrigerant circuit is empty and the A/C compressor idles with the engine.
If it is necessary to start the engine with a discharged refrigerant circuit:
The refrigerant circuit must be fully assembled.
At least a quarter of the prescribed refrigerant oil must be in the A/C compressor.
The engine speed must not exceed 2000 RPM.
The engine should only run as long as absolutely necessary, maximum 10 minutes.