Refrigerant Circuit Component Overview
Refrigerant Circuit Component Overview
• Repair work on refrigerant circuit, refer to=> [ Refrigerant Circuit Repairs ] Refrigerant Circuit Repairs.
• All work or components marked with 1) can be repaired, replaced or performed in any workshop (work that does not pertain to refrigerant circuit).
• All refrigerant circuit components not marked with 1) as well as all refrigerant hoses and refrigerant lines can only be serviced or replaced in a workshop equipped with the necessary tools and in which the work procedures are performed by qualified personnel (refrigerant circuit must be discharged).
• In this repair information, the Guided Fault Finding functions (Checking the DTC memory, output Diagnostic Test Mode (DTM), Basic Setting Coding, Reading Measuring Value block and Adaptation) wiring and component test of the A/C system components are not described. Perform electrical testing via "Guided Fault Finding" function, here can also be found notes on the functions which should be tested.
• Temperature-dependent resistance values of the various temperature sensors are stored in one table, this can be called up via the "Guided Fault Finding" function of the Vehicle diagnosis, testing and information system (VAS5051B) in "Guided Fault Finding".
HD = High-pressure end
ND = Low-pressure end
1 - A/C Compressor Regulator Valve (N280)
• Checking activation and function. Refer to=> [ A/C Compressor Regulator Valve (N280), Checking Switch-On Signal ] A/C Compressor Regulator Valve (N280), Checking Switch-On Signal 1).
2 - A/C Compressor
• Remove A/C compressor from and reinstall onto the bracket. Refer to => [ Compressor, Removing From Bracket ] Compressor, Removing From Bracket 1).
• When installing refrigerant lines/hoses and pertaining bracket, make sure there is a sufficient gap between belt, bracket and belt pulley.
• Depending on time period of production and on engine, compressor construction type may vary. Refer to Electronic Parts Catalog (ETKA).
• A/C compressors made by Denso (type 7 SEU 16 or 7 SEU 17) were installed at Start Of Production (SOP). Starting with MY 04 A/C compressors made by other manufacturers (Delphi, Sanden or Zexel / Valeo) were installed. Refer to=> Electronic Parts Catalog.
• These A/C compressors are available as replacement parts with different oil fill capacities, therefore note capacity on the A/C compressor and the exact part number. Refer to the Electronic Parts Catalog.
• Depending on A/C compressor type, different refrigerant oil fill capacities are designated for the refrigerant circuit. The reason for the different oil capacities in the A/C compressor for an otherwise identical refrigerant circuit lies in the design of the A/C compressor itself, note these oil capacities. Too much oil in the circuit leads to higher pressures and reduces cooling performance of the system. Too little oil may lead to lubrication problems in the compressor.
• Beginning the production year 2006, the name of the Zexel A/C compressor was changed from Zexel to Valeo.
3 - Belt Pulley
• Replace 1). Refer to => [ A/C Compressor and Pulley ] Service and Repair.
• Ribbed belt, removing and installing 1).
• Ribbed Belt Routing. Refer to Electronic Parts Catalog (ETKA).
• There is an overload protection installed between the belt pulley and the A/C compressor input shaft to protect the belt should the A/C compressor get blocked or be difficult to move.
• If the A/C compressor is runs with resistance, the overload safeguard interrupts the supply of power to it.
• Rubber elements are installed between belt pulley and A/C compressor driveshaft, vibrations which may occur during A/C compressor operation may be dissipated via these rubber elements (damper function at torque fluctuations).
• Depending on A/C compressor, different belt pulleys are installed on compressor. Refer to => [ A/C Compressor and Pulley ] Service and Repair.
• The Delphi A/C compressor belt pulley cannot be removed separately.
4 - Oil Drain Plug
5 - Pressure Relief Valve
6 - Connection With Valve
• Different component locations depending on engine, item 6a shows component location e.g. in vehicles with 2.0 L Diesel engine
7 - High Pressure Sensor (G65) 1)
• Removing and installing, refer to => [ High Pressure Sensor (G65) ] Service and Repair.
• Checking signal, refer to=> [ High Pressure Sensor (G65), Checking Pressure Signal ] Testing and Inspection.
• Different component locations depending on engine, item 7a shows component location, for example, in vehicles with 2.0 L Diesel engine.
8 - Condenser
• In vehicles with rough terrain equipment, an additional stone deflector may be installed in lower area.
9 - Fluid Reservoir
• Fluid reservoir is mounted directly on the condenser.
10 - Service Connection
• High pressure side.
• For the A/C service station to measure pressures, to discharge and recharge the refrigerant circuit.
• Depending on engine version, it may be necessary to remove some components (for example, EVAP canister) in order to be able to connect to service coupling.
Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve.
11 - Sealing Cap
• With a seal
• Always screw on
12 - Expansion Valve
13 - Evaporator
14 - Service Connection
• Low pressure side.
• Depending on engine version, it may be necessary to remove some components (for example, EVAP canister) in order to be able to connect to service coupling.
Only remove service connections when the refrigerant circuit is empty. The connection does not have a valve.
15 - Sealing cap
• with a seal
• Always screw on
16 - Pre-volume
• Is a component of refrigerant line from expansion valve to A/C compressor.
• Pressure fluctuations are damped in the damping chamber.
• Not installed in all vehicles (currently not installed on the 2.0L diesel engine).
17 - Connection In Refrigerant Line
• Not installed on all vehicles (currently, for example, installed on 6 cylinder vehicles).