Troubleshooting The Air-Conditioning System Following A Complaint About Noises

Information 

The troubleshooting steps shown must be used if complaints are received about noises in the air-conditioning system.

> 8X00IN INSTRUCTIONS FOR REPAIRING AIR-CONDITIONING SYSTEMS AND STORING SPARE PARTS

Information 

Leaking air-conditioning systems must only be filled with nitrogen or forming gas for the purposes of leak testing.

Leak detector additives must only be used if there is no clear indication from the leak test using nitrogen or forming gas.

Leak detector additives from Waeco are compressor oils with fluorescent components and meet the requirements for the operational fluids and fuels.

Only compressor oils with fluorescent components may be used as leak detector additives.

Leak detector additive: Tracer UV additive (500 ml container) TP-3525-500 specifically for Waeco air conditioning service equipment. 

Leak detector additive: Tracer UV additive (stick) TP-9825-0301; can be used universally for all air conditioning service equipment. 

For vehicles with refrigerant R134a, the leak detector additive Traserline TP 3860 in dissolved form can also be used.

Special adapter kits are required for filling the Tracer UV additive (stick) TP-9825-0301 and Traserline TP 3860; these are also available from air conditioning service equipment providers (e.g. Waeco).

Fluorinated greenhouse gases are not permitted in leak testing. 

Instructions for use and the procedure for filling the air-conditioning system can be found in the operating instructions provided by the respective air conditioning service equipment provider.

Condition	Specification OK	Specification not OK
1) Check for noises from around the compressor. Start the engine and switch on air conditioning.	No unusual operating noises can be heard from the air-conditioning system. Continue with Step 2)  .	Noises coming from the air-conditioning system. > > Mechanical noises, continue with Step 3)  If you have already carried out Step 3), continue with Step 5)  > > Squeaking noises, continue with Step 4)
2) Start the vehicle and check the air-conditioning system for the prescribed nominal temperature values. > 8701IN Nominal values for pressures and temperatures	Nominal values OK and no noises from the air-conditioning system. Function OK. No further action required.	Nominal values not OK, proceed according to "Troubleshooting the air-conditioning system following complaints about cooling output".
3) Check the following points one after the other: Remove drive belt and check condition. Check the bearing clearance of the pulley. Check refrigerant level. Drain refrigerant and measure the amount of refrigerant. >> Not enough refrigerant. > WM, 870317 DRAINING AND FILLING REFRIGERANT R134A , WM, 870317 DRAINING AND FILLING REFRIGERANT R1234YF		Replace drive belt if necessary. Replace pulley if necessary. Fill the air-conditioning system with the prescribed amount of refrigerant. > 8700IN Technical data for air-conditioning system  Check refrigerant circuit and connection points using a leak detector. >> Once you have determined the cause of refrigerant loss, replace seal or spare part. Continue with Step 1)
4) Remove drive belt and check for signs of wear or damage.	Systematically broaden the check to determine if there are noises coming from other components.	Replace drive belt if necessary. Continue with Step 1)
5) Replace air-conditioning compressor. > WM, 873419 REMOVING AND INSTALLING AIR CONDITIONING COMPRESSOR	Function OK. No further action required.