Plenum Chamber Water Drain, Checking
On vehicles with a high voltage system (hybrid vehicles)
Observe all of the additional warnings for all work performed on vehicles with the high voltage system. Refer to HIGH VOLTAGE VEHICLES SAFETY PRECAUTIONS and HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
If it is necessary for the following procedure to perform work near 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 "always follow the warnings when working on the high voltage system". Refer to 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.
-- Turn off the ignition.
-- Remove the rubber seal -A- and plenum chamber cover -B- (different versions). Refer to PLENUM CHAMBER COVER, REMOVING AND INSTALLING .
- Visually inspect the high voltage components -D- (here the Electric Drive Power and Control Electronics -JX1-) and the high voltage cables -E- after removing the plenum chamber cover -B-. Refer to PERFORMING A VISUAL INSPECTION OF DAMAGE TO HIGH VOLTAGE COMPONENTS AND CABLES and HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
- Be careful not to damage any high voltage components -D- or the high voltage cables -E-. Refer to HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
- Visually inspect the high voltage components -D- and high voltage cables -E- after completing the work procedures and before installing the plenum chamber cover -B-. Refer to HIGH VOLTAGE SYSTEM GENERAL WARNINGS .
For vehicles without a high voltage system
-- Turn off the ignition.
-- Remove the plenum chamber cover and/or the cowl panel trim (different versions). Refer to PLENUM CHAMBER COVER, REMOVING AND INSTALLING -item 1- .
All vehicles
The following illustrations show the location of the components on an Audi A5 Coupe; an Audi A5 Sportback, Audi A4, Audi Q5 etc., the location of the components varies slightly. The description of the components is not different; removing, installing and checking is performed in the same way as on the Audi A5 Coupe.
The draining of water from plenum chamber may be impaired by deposits (leaves, diverse tree needles etc.) accumulating in plenum chamber water drains -A-. The water level in the plenum chamber then rises if the vehicle is taken to an automatic car wash or in the event of heavy rain, water enters via intake housing into the A/C unit and is blown by the Fresh Air Blower -V2- onto the evaporator together with the air conveyed.
If both water drain grommets -A- (right and left in plenum chamber) are blocked by leaves and pine needles, it may cause the drains to freeze up in winter and water can no longer drain out. After a short drive, heat emitted from engine and exhaust system melts the ice in the drains again and water may drain off again before vehicle arrives at the workshop.
The water drain grommets -A- are snapped into the plenum chamber openings from above.
In addition to the two water drain grommets -A- there is an opening on the right side of the body -C- in which water can drain out behind the wheel housing in case both water drain grommets -A- should become obstructed. Likewise, make sure these openings are not obstructed by dirt.
-- Check the function of the -A- grommets (the valves -B- must not stick or be obstructed with dirt)
To check the water drains that are difficult to reach, use a commercially available and illuminated endoscope, for example. It is best to use one that has a flexible waterproof head.