General Information: Notes
Vehicles with a High Voltage System (Hybrid Vehicles)
Read and follow all of the supplemental warnings for all work performed on vehicles with the high voltage system. Refer to WARNINGS WHEN WORKING ON VEHICLES WITH HIGH VOLTAGE SYSTEM and HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
Risk of unintended engine start
The ignition must be turned off and the ignition key must remain outside of the vehicle when working on vehicles with a high voltage system.
Handling high voltage cables:
- Do not stand on or place tools on high voltage cables and their components as it may damage the cable insulation.
- Never bend or kink high voltage cables forcefully as it may damage the cable insulation.
- The round high voltage connectors are color coded with an external color ring and are mechanically coded using the guide- or code tabs. Always make certain that the coding matches when connecting the round connector in order to avoid any mechanical damage the high voltage connector.
There is a risk of electrocution from damaged high voltage components.
Observe the following when working around high voltage components and high voltage wires:
- Never work around high voltage components and cables with cutting, deformed, or sharp edged tools, or heat sources such as welding or soldering tools, heated air, and thermal glue.
- Inspect the high voltage components visually before beginning.
- Perform a visual inspection of the Electric Drive Power and Control Electronics -JX1-, the Electro-Drive Drive Motor -V141-, the Electrical A/C Compressor -V470- and the high voltage lines when working in the engine compartment.
- Perform a visual inspection of the high voltage lines and covers when working on the underbody.
- Perform a visual inspection of the high voltage lines and the Electrobox with the High Voltage System Maintenance Connector -TW- when working in the luggage compartment.
- Perform a visual inspection on all of the potential equalization cables.
Observe the following items when performing the visual inspection:
- The components do not display any signs of external damage.
- The high voltage cable insulation and the potential equalization cables are not damaged.
- The high voltage cables do not display any abnormal deformations.
- Every high voltage component is marked with a red warning label.
If it is necessary to perform work in the vicinity of high voltage components, perform a "visual inspection" of the high voltage components and cables for damages (refer to PERFORMING A VISUAL INSPECTION OF DAMAGE TO HIGH VOLTAGE COMPONENTS AND CABLES ) and follow the "WARNINGS WHEN WORKING ON VEHICLES WITH HIGH VOLTAGE SYSTEM ". Refer to HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
If it is necessary to perform work on the high voltage components, disable the high voltage system. Refer to HIGH VOLTAGE SYSTEM, DE-ENERGIZING and read and follow the "high voltage electrical system general warnings", refer to HIGH VOLTAGE SYSTEM GENERAL WARNINGS and WORKING ON HIGH VOLTAGE VEHICLES .
Disable the high voltage system
Risk of electrocution
Death or serious bodily injury by electric shock.
- The high voltage system may only be activated by qualified personnel (Audi high voltage mechanic).
- Make sure that the high voltage system is completely disabled. Make sure the vehicle is de-energized using "Guided Fault Finding " on the Vehicle Diagnostic Tester.
- The qualified personal (Audi high voltage technician) determines the voltage and secures the system from restarting using the Service Disconnect Lock T40262. Keep the ignition key and the High Voltage System Maintenance Connector -TW- safely with the qualified personal to secure the system from restarting.
- The Audi high voltage technician should put a sign on the vehicle to identify it as a high voltage vehicle.
Disable the high voltage system:
Connect the Vehicle Diagnostic Tester.
Select the Guided Fault Finding mode.
Using the GO TO button, select the following menu commands
Function/Component Selection
Body
Electrical Equipment
OBD-capable systems
8C - Battery Regulation Control Module -J840
8C - Battery Regulation Control Module, functions
51 - De-energize the high voltage
High-Voltage System, Re-Energizing
Risk of electrocution
Death or serious bodily injury by electric shock
- The high voltage system may only be restarted by qualified personal (Audi high voltage technicians).
- Make sure the vehicle is energized using the "Guided Fault Finding " on the Vehicle Diagnostic Tester.
- The qualified personal (Audi high voltage technician) restarts the vehicle.
- The Audi high voltage technician should put a sign on the vehicle to identify it as a high voltage vehicle.
Restart the high voltage system:
Connect the Vehicle Diagnostic Tester.
Select the Guided Fault Finding mode.
Using the GO TO button, select the following menu commands
Function/Component Selection
Body
Electrical Equipment
OBD-capable systems
8C - Battery Regulation Control Module -J840
8C - Battery Regulation Control Module, functions
51 - High voltage restart
The engine may start unexpectedly when performing work while the ignition is turned on or when the ready mode is activated and may cause poisoning in enclosed spaces. Be aware of body limbs and/or clothing when clamping or pulling.
Perform the following steps before turning on the ignition:
- Move the selector lever into position P.
- Activate the parking brake.
- Switch off ignition.
- Open the engine hood.
- Connect the charging unit for example Battery Charger VAS 5095A to the battery jump start terminal for the 12V vehicle electrical system
- Switch on the ignition.
-- Charge the vehicle battery, for example, using the Battery Charger VAS5904 in the battery support mode to minimize the number of automatic starts during the test- and measuring procedures while the ready mode is active. Refer to Battery Charger VAS5900 SUPPORT MODE and HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
-- Move the selector level into position "P", activate the parking brake and arrange the necessary tools for testing and measuring procedures that require the ready mode to be active or that require the ignition to be on, so that they cannot come into contact with the turning components in the engine and so that they are not in the vicinity of the turning components of a running engine.
Also move the selector lever into position "P" and activate the parking brake for testing and measuring procedures which require the ignition to be on, but do not require the ready mode to be active.
The ready mode is displayed in the Instrument Cluster Control Module -J285- above the "powermeter". Refer to Owner's Manual.
Activate and deactivate the ready mode. Refer to Owner's Manual (consult the display in the Instrument Cluster Control Module -J285-).
All Vehicles
- If it is suspected that chemicals were added to the refrigerant circuit to seal leaks, chemical substances to seal leaks in the refrigerant circuit (leak stop additive), do not connect the A/C service station, do not extract the refrigerant and do not clean (flush).
- Chemicals that seal leaks in the coolant circuit form deposits that affect the function of the A/C system and lead to failure of the A/C system and the A/C service station.
- Inform that customer that there are substances in the A/C system that are no approved by Volkswagen and for this reason the climate control system cannot be cleaned (flushed) or serviced.
Audi does not approve the use of chemicals to seal leaks in the refrigerant circuit (leak stop additives).
Chemical materials (leak stop additives) to seal leaks in the refrigerant circuit react with air or the moisture in the air and form deposits in the refrigerant circuit (and in the A/C service station) that lead to malfunctions in the valves and other components that come into contact with such chemicals. These deposits cannot be removed completely from the components, even by cleaning/flushing. It is only possible to service the refrigerant circuit by replacing all the components which come in contact with this material.
It is not possible to recognize chemical substances to seal leaks in the refrigerant circuit (leak stop additive) and the label that is supposed to come with them is usually not there. Therefore be careful when working with if you do not know its service history.
- Refrigerant circuit must be cleaned (flushed) with refrigerant R134a in order to force out moisture and other contaminants as well as old refrigerant oil as efficiently as possible, without wasting refrigerant, without the need for extensive assembly work and without endangering the environment.
Flush the refrigerant circuit:
-- In the event of dirt or other contamination in the circuit.
-- If vacuum reading is not maintained on evacuating a leak-free refrigerant circuit (pressure build-up due to moisture in refrigerant circuit).
-- The refrigerant circuit has been left open for longer than normal (for example, following an accident).
-- Pressure and temperature measurements in the refrigerant circuit indicate the likelihood of moisture.
-- In the event of doubt about the amount of refrigerant oil in the circuit.
-- The A/C compressor had to be replaced on account of internal damage (for example, noise or no output).
Pay attentions when replacing the Electrical A/C Compressor -V470- on vehicles with electrically driven A/C compressor (if the electronic on the A/C compressor is damaged the refrigerant circuit must not always be cleaned. Refer to COMPRESSOR, REPLACING WITHOUT THE NEED FOR FLUSHING REFRIGERANT CIRCUIT .
If a faulty A/C compressor is replaced with an A/C compressor from another manufacturer check for the A/C compressor to be installed has the same refrigerant oil approved which is already in the refrigerant circuit (from the removed A/C compressor). If a different refrigerant oil is approved for the A/C compressor to be installed then the A/C compressor which was removed, the refrigerant circuit must be flushed. Refer to APPROVED REFRIGERANT OILS .
-- If it is stipulated by the vehicle-specific repair information following the replacement of certain components.
Tools required
- A/C Service Station with Flushing Device (on these A/C service stations, the auxiliary function "flush refrigerant circuit" and the refrigerant circuit flushing device required for it are present on these A/C service stations). (Refer to Tools; Special Tools and Equipment: A/C and Heating).
- Refrigerant Circuits Adapter Set 1 VAS6338/1. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and (Refer to Tools; Special Tools and Equipment: A/C and Heating).
If a A/C Service Station with Flushing Device is not available (refer to Tools; Special Tools and Equipment: A/C and Heating), it is possible to flush the refrigerant circuit with (with refrigerant R134a) the flushing device available using Refrigerant Circuit Flushing Device (Refer to Tools; Special Tools and Equipment: A/C and Heating), however the procedure must be done manually. Refer to "*Sequence of flushing procedure (sequence occurs automatically according to the A/C service station program) ".
On vehicles with screw connections on the refrigerant circuit, the A/C Adapter Set Adapter 7 VAG1785/7 and A/C Adapter Set Adapter 8 VAG1785/8 from Refrigerant Circuits Adapter Set 1 VAS6338/1 can be used; on vehicles with screw connections at the A/C compressor and reservoir, two A/C Adapter Set - Adapter 8 VAG1785/8 are required.
In Refrigerant Circuits Adapter Set 1 VAS6338/1, there is also a Refrigerant Circuits Adapter Set 1 - Adapter 31 VAS6338/31 with connections 5/8 -18 UNF and large inner diameter in short version (commercially available).
Preliminary Work
-- Discharge refrigerant circuit. Refer to REFRIGERANT CIRCUIT, DISCHARGING WITH SERVICE STATION .
-- Remove the A/C compressor. Refer to A/C COMPRESSOR (vehicle-specific repair information).
On a vehicle with restrictor and reservoir
-- Remove restrictor (vehicle-specific) and reconnect lines OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
-- Remove reservoir (vehicle-specific) and reconnect the lines (use adapters and Refrigerant Circuits Adapter Set 1 - Adapter 31 VAS6338/31 from the Refrigerant Circuits Adapter Set 1 VAS6338/1). Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
Depending on the version, the reservoir could be potentially flushed but it will take too much refrigerant because of its large internal volume; the reservoir would ice-up too much when extracting the refrigerant, the refrigerant would evaporate too slowly and the extraction process would take too long.
Depending on the version, the receiver/dryer can be potentially flushed (see vehicle-specific description) but it will take too much refrigerant because of its large internal volume; the receiver/dryer would ice-up too much when extracting the refrigerant, the refrigerant would evaporate too slowly and the extraction process would take too long.
On a vehicle with expansion valve and receiver/dryer
-- Remove receiver/dryer (vehicle-specific, not necessity on all vehicles) and reconnect the lines (use adapters and Refrigerant Circuits Adapter Set 1 - Adapter 31 VAS6338/31 from the Refrigerant Circuits Adapter Set 1 VAS6338/1). Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and [[Editorial:Find destination]] (vehicle-specific repair information).
The receiver/dryer can be flushed depending on the version (remove dryer cartridge if necessary). Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
The receiver/dryer connected to the condenser (for example on model Audi A3 from model year 2004) remains installed during flushing (it can be flushed due to its design and is only replaced after flushing). Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
If the receiver/dryer or dryer cartridge is integrated in the condenser, then they cannot be replaced separately or are not available as a single part, and the condenser must be replaced. Replace the condenser with the receiver/dryer on these vehicles. Refer to OVERVIEW - REFRIGERANT CIRCUIT .
Receivers/dryers where it is possible to replace the dryer cartridge have an additional filter, which must also be replaced with the dryer cartridge.
-- Remove dryer cartridge from vehicles with dryer partridge in receiver/dryer that is connected to the condenser (vehicle-specific), and seal opening on receiver/dryer. Refer to OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
-- Remove expansion valve (vehicle-specific) and install one adapter from the Refrigerant Circuits Adapter Set 1 VAS6338/1. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
-- On vehicles with a shut-off valve install the valve and the adapter (or a hand shut-off valve) from the Refrigerant Circuits Adapter Set 1 VAS6338/1 (or a drilled open shut-off valve). Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
*If there is no adapter suitable for the expansion valve (or the shut-off valve) in the Refrigerant Circuits Adapter Set 1 VAS6338/1, the removed expansion valve (of the shut-off valve) can also be drilled open (the old expansion valve must be replaced in most cases and is therefore no longer required).
- Make sure the sealing surfaces on the expansion valve (or the shut-off valve) are not damaged when drilling open.
- Refrigerant will otherwise escape if the sealing surface is damaged.
Drill a hole for the expansion valve.
Before drilling open, remove the regulating element and drill open the expansion valve using a suitable drill, for example (drill bit diameter 6.0 mm, for example).
Several components are to be removed from expansion valve before drilling open.
Expansion valves are available in various versions and with different constructions. For version -A-, for example. parts -B-, -C- and -D- must be removed. Separate part -E- (regulating element) from component -D-. Then drill open expansion valve in area -F- using a suitable drill.
For version -G- for example, parts -H-, -I- and -K- must be removed and then drill the open area -L- using a suitable drill.
-- Clean the drilled open expansion valve of residue from the work (shavings).
-- Install the parts -B-, -C- and -D- for version -A-, or the part -H- for version -G-.
On vehicles with two evaporators, disconnect second evaporator circuit from first evaporator circuit and flush separately. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT and OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
Drilling open the shut-off valve.
If the Shut-Off Valves VAS6338/42 is not available to flush, then a shut-off valve, for example, is to be drilled out.
-- Remove the solenoid coil -A- and the solenoid valve -B- before drilling open.
-- Drill open the shut-off valve -C- using a suitable drill (diameter of the drill for example 5.0 mm).
-- Clean the shut-off valve -C- from shavings produced by drilling -D-.
-- Install the solenoid valve -B- with the seals belonging to it -E- on the drilled open shut-off valve -C-.
Flushing
-- Check refrigerant quantity in the A/C service station, there must be at least 7 kg of refrigerant R134a.
If necessary, turn on the heating installed in the service station for the refrigerant container before the first flushing (to increase the pressure in the refrigerant container) and turn it off before first extraction during flushing.
-- Drain the old oil container of the A/C service station.
-- Connect the supply hose (high pressure side) of A/C service station to the low pressure line leading to the A/C compressor (line with larger diameter) using an adapter. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .
-- Connect the return hose (low pressure- or intake side) of the A/C service station to the output of the refrigerant circuit flushing device.
-- Connect the input on the refrigerant circuit flushing device to the high pressure line leading to the A/C compressor (line with smaller diameter) using an adapter. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .
Components are always (with the exception of the electrical A/C compressor) flushed in the opposite direction of refrigerant flow when the A/C system is in operation. Refer to FLUSHING CIRCUIT BLOCK DIAGRAMS .
While flushing, contaminants from the refrigerant circuit enter the refrigerant circuit flushing device and the A/C service station and are absorbed by the filters and dryers installed there. Depending on the contaminant, these components are to be replaced in shorter intervals in line with operating instructions for A/C service station or refrigerant circuit flushing device.
The filter in the refrigerant circuit flushing device depends on the type and degree of contamination in the flushed refrigerant circuit, it should be changed after five to ten flushing cycles (flushed vehicles) at the latest. If a heavily contaminated refrigerant circuit is flushed (the refrigerant oil from the circuit is black and viscous or there are many shavings in the refrigerant circuit), the filter should be replaced after flushing. With a refrigerant circuit heavily contaminated in this way, it is wise to flush the circuit again after changing the filter.
Depending on the type of contamination, dirt (old refrigerant oil and abraded material from A/C compressor) is deposited on the viewing glass. Clean the viewing glass after flushing if necessary, and flush the refrigerant circuit once more with one flushing procedure as a check (one cycle is sufficient).
Liquid refrigerant cannot be led through the expansion valve, restrictor and dryer bag of certain receiver/dryers at an appropriate speed, therefore these components must be removed and replaced by adapters if necessary OVERVIEW - REFRIGERANT CIRCUIT (vehicle-specific repair information).
For adapters for connecting the A/C service station and for bridging certain components of refrigerant circuit. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .
-- Turn on the A/C service station and flush the refrigerant circuit (duration approximately one to one and a half hours for one flushing cycle with three flushing operations).
Perform flushing procedure according to operating instructions of the A/C service station. Refer to the operating instructions for the A/C service station.
Depending on version of A/C service station, old oil container holds only approximately 125 cm 3 refrigerant oil, in the event a system with a larger quantity of refrigerant oil must be flushed, it may be necessary to drain the old oil container after the first flushing process of one flushing cycle.
Observe the refrigerant which flows back into the A/C service station from the refrigerant circuit, only when the refrigerant streams clear and completely colorless through the viewing glass of refrigerant circuit flushing device into the A/C service station is the refrigerant circuit cleaned.
While flushing, all the refrigerant oil is washed out of the refrigerant circuit (up to a very small amount, for example in the evaporator, however this can be disregarded).
If heavily contaminated, it may be necessary to perform the flushing procedure twice (two flushing cycles with three flushing operations each).