Volkswagen Tiguan Service and Repair Manual: Concerns

Possible Refrigerant Circuit Concerns

Test Requirements

Note

• The A/C system is functioning correctly when the air flowing from the instrument panel vents has a temperature of 7⁰C or lower.
• Setting on Climatronic "LO".
• Setting on A/C system "AC" on; "max"; "cold".
• The A/C system OBD cannot find malfunctions with the Vehicle Diagnostic Tester in "Guided Fault Finding". The measured value block does not show any shut-off condition for the A/C compressor (only on vehicles with "A/C system" OBD).

Possible Concerns

Note

• The A/C system is functioning correctly when the air flowing from the instrument panel vents has a temperature of 7⁰C or lower.
• Setting on Climatronic "LO".
• Setting on A/C system "AC" on; "max"; "cold".

Note

With all complaints marked with *.

• Total cooling system failure. *
• Insufficient cooling performance at all vehicles speeds or engine speeds. *
• None or insufficient cooling after driving a few miles. *
• A/C compressor, A/C Clutch -N25- or A/C Compressor Regulator Valve -N280- are switched off by A/C Refrigerant Low Pressure Switch -F73-, A/C Refrigerant High Pressure Switch -F118-, A/C Pressure Switch -F129- or by A/C Control Head -E87- or Climatronic Control Module -J255- due to excessive or insufficient pressure. *
• None or sharp decrease in fresh-air supply after driving several miles (evaporator iced up). *

From these, the following complaints may also occur:

The A/C compressor makes noises

• Re-tighten compressor securing bolts and compressor bracket using a torque wrench.
• Check routing of refrigerant lines; they must not touch other components and must not be subject to strain (align if necessary).

Noise (refrigerant hammer) occurring immediately after switching on air conditioner and/or when cornering or braking:

• Discharge, evacuate and charge refrigerant circuit (too much refrigerant in circuit).

Note

• Too much refrigerant oil in the circuit could also cause this problem. This could occur if the amount of refrigerant oil was not adjusted when replacing the A/C compressor. If this occurs, flush the refrigerant circuit with refrigerant R134a.
• Drain the refrigerant from the A/C compressor. To facilitate this, the ribbed belt pulley or magnetic clutch plate on the A/C compressor should be rotated by hand. After flushing, the entire quantity of refrigerant oil specified by vehicle-specific repair manual should be added to the refrigerant circuit (50 grams directly in the A/C compressor).

Water sprays out of vents (in dash panel or footwell) although air conditioning system is otherwise functioning properly:

• Check proper routing of condensate drain; it must not be crushed or kinked.
• Check condensation drain valve, it must not be clogged by wax or underbody sealant and must open and close properly.
• Check plenum chamber cover; it must not be damaged and must be properly installed (to stop water running into evaporator).
• Check water drains in plenum chamber; they must not be blocked (e.g. by leaves).

Odor from the Heater and A/C Unit

Odor from Evaporator or Heat Exchanger?

• Fishy smell

• From leak at cooling system of engine or of A/C system heater core.

Note

If the fishy smell gets weaker when the temperature is set to "cold" and stronger when it is set to "warm", then check the heat exchanger for leaks.

• Smells like a burned clutch.
• Evaporation from floor mats, decorative seat covers, etc.
• Musty smell

• Due to various contaminants, such as leaves, pine needles, etc. collecting.

Note

Clean the plenum chamber.

• Due to water that cannot drain out of the plenum chamber.

Note

Check that the plenum chamber water is draining.

• Odor from the Heater and A/C Unit

Note

Odors originating in the heating and A/C unit can mainly be detected in fresh air mode and recirculated air mode.

• Due to too much condensation water in A/C unit.

Note

Check the condensation water drain.

• Due to an old or heavily contaminated dust and pollen filter.

Note

Check the dust and pollen filter.

• Due to deposits on evaporator fins.

Note

Clean the evaporator using the Ultrasound A/C Cleaner -VAS6189A-.

Ultrasound A/C Cleaner -VAS6189B-

• The Ultrasonic HVAC Cleaning System -VAS6189A- is placed in the front passenger footwell and sprays Aero-Clean. Aero-Clean neutralizes microbes and bacteria inside the heater and A/C unit.

The unit comes with Operating Instructions.

Evaporator, Cleaning with Suction Feed Spray Gun -VAG1538- and Spray Nozzle

Spray off the evaporator directly with Contra Sept using a spray nozzle (approximately 10 bar (145 psi) ). Contra Sept neutralizes microbes and bacteria directly on the evaporator.

To make it possible to access the evaporator, some prework and different spray nozzles are needed, for example VAG1538/5;VAG1538/6 orVAG1538/7.

A vehicle-specific instruction booklet is included with the evaporator cleaning solution D 600 100 A2

Connecting Service Station

Refrigerant Circuit, Connection on Low and High Pressure Side

A/C Service Station, Connecting for Measuring and Testing

• Turn off the ignition.
• Connect the A/C service station to the power supply.
• Connect quick-release coupling adapter to charging hoses of service station (handwheels not screwed in/hand shut-off valve not open).
• Switch on service station and evacuate charging hoses (only necessary if there is air in charging hoses).
• Switch off A/C service station.
• Remove caps from service connections (with valve).
• Connect the A/C service station to the refrigerant circuit using service connections with quick-release coupling adapters.
• Screw in handwheel of quick-release coupling adapters only until valves are definitely open at refrigerant circuit connection (observe pressure gauge, do not strain valves).
• Perform planned tests and measurements.