audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

ABOUT US
Removing auxiliary heater > < Removing and installing heater coolant shut-off valve N279

A4 Mk3

Removing and installing auxiliary heater
Removing and installing auxiliary heater
  WARNING
The cooling system is pressurised. When the engine is warm, the coolant temperature may be in excess of 90 °C. Dissipate pressure and allow to cool down before performing repairs. Dissipate the pressure in the coolant circuit by opening the cap at the coolant expansion tank → Engine, mechanics; Rep. Gr.19.
  Note
t  On replacement, pay attention to the correct auxiliary heater version (different design for vehicles with petrol or diesel engine) → Chapter.
t  The Audi A5 Coupé and the Audi A4 as of Model Year 2009 are gradually being fitted with modified auxiliary heaters with an adapted supplementary heater control unit -J364- (these were installed on the Audi Q5 right from the start of production). Pay attention to correct assignment of these components to the vehicle → Electronic parts catalogue and → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  This auxiliary heater is installed in various vehicle models. The part number changes each time this auxiliary heater is fitted in a new vehicle model (e.g. from 8K0 xxx xxx to 8R0 xxx xxx on introduction of the Audi Q5 and subsequently to 4xx xxx xxx etc.). Attention must therefore be paid to correct assignment. Care must however also be taken to ensure that an old auxiliary heater version is never installed in a vehicle previously fitted with a newer version. For example, an Audi A4 provided at the factory with an auxiliary heater with part number 8R0 xxx xxx is not to be fitted with an auxiliary heater with part number 8K0 xxx xxx → Electronic parts catalogue.
t  As of 10.2010 auxiliary heaters with part number 4xx xxx  xxx are gradually to be introduced. Service installation of this version of the auxiliary heater is also possible in vehicles originally fitted with an auxiliary heater with part number 8R0 xxx xxx or 8K0 xxx xxx. As however there are differences between certain components of the various auxiliary heater versions (e.g. the 2-pin connector for the power supply to the auxiliary heater control unit -J364-), attention must be paid to correct assignment when replacing individual components of the auxiliary heater → Electronic parts catalogue.
t  If an auxiliary heater with part number 4xx xxx  xxx is fitted, attention must also be paid with this version to correct encoding for the vehicle concerned (different functions are stored in the control unit depending on the type of vehicle encoded) → Electronic parts catalogue and → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
   
t  The Audi A4, A5 and Q5 are currently provided with an auxiliary heater remote control hand transmitter with no display → Owner's manual.
t  Auxiliary heaters with an auxiliary heater control unit -J364- with part number 8xx xxx. xxx are only designed for actuation by way of a hand transmitter with no display. As of 10.2010, auxiliary heaters with a -J364- with part number 4xx xxx  xxx are gradually being introduced. With these auxiliary heaters, the version of the hand transmitter (with or without display) must have been properly encoded in -J364-. This also applies to service replacement of a -J364- with part number 8xx xxx  xxx by a -J364- with part number 4xx xxx  xxx → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”
t  As of Model Year 2010 a start/stop system will be available as an optional extra for this vehicle in conjunction with certain engines. On these vehicles, pay attention to the correct version of the air conditioner operating and display unit, Climatronic control unit -J255- and of the auxiliary heater → Electronic parts catalogue and → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
t  Vehicles with a start/stop system are not to be fitted with auxiliary heaters with part number 8K0 xxx xxx → Electronic parts catalogue and → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
t  On vehicles with a start/stop system the circulation pump -V55- of the auxiliary heater is actuated during the stop function by the supplementary heater control unit -J364-. Via the data bus, -J364- is requested by the air conditioner operating and display unit, Climatronic control unit -J255- to switch on -V55- → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051
t  If the assignment of the supplementary heater control unit -J364- (rating plate) differs from the information given on the fault reader display, check the display in the measured value block → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  If the auxiliary heater is replaced (together with the supplementary heater control unit -J364-), check operation of at least one remote control hand transmitter (if operation is not OK, all hand transmitters are to be re-adapted by way of the supplementary heater control unit -J364-) → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function” and → Chapter.
t  If the auxiliary heater has been replaced (together with the auxiliary heater control unit -J364-), perform auxiliary heater guided fault-finding after installing the auxiliary heater (interrogate event recorder, perform basic setting, check encoding and adaption etc.) → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  If auxiliary heater components have been replaced (e.g. the combustion air blower -V6-), check the CO2 content in the auxiliary heater exhaust gas.
t  If, depending on the version of the supplementary heater control unit -J364-, the auxiliary heater cannot be activated on a new vehicle or in the case of a newly installed auxiliary heater, the component protection function may be active (if a large number of faults occurred simultaneously at some point, this fault may no longer be displayed although it is still active). If necessary, perform re-adaption of the component protection function as for a newly installed auxiliary heater to cancel component protection → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  There are different auxiliary heater versions. The Audi Q5 is not to be fitted with auxiliary heaters with part number 8K0.xxx.xxx. Pay attention to the exact assignment when replacing an auxiliary heater → Chapter and → Electronic parts catalogue.
t  If the auxiliary heater is to be replaced, interrogate the encoding and adaption of the supplementary heater control unit -J364- by way of the “Control unit replacement” function of the guided fault-finding routine prior to removal (the supplementary heater control unit -J364- is installed in the heater) → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding” function.
t  The holders for the auxiliary heater were gradually modified on the Audi Q5 in Model Year 2009. Pay attention to the correct assignment when replacing the auxiliary heater and holders → Electronic parts catalogue and → Anchor.
After installing the auxiliary heater, perform the following checks/make the following settings depending on the repair work involved:
–  Check/enter the encoding of the supplementary heater control unit -J364- → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
–  Interrogate the adaption of the supplementary heater control unit -J364- and perform adaption for the supplementary heater control unit -J364- if necessary (pay attention to any customer-specific settings) → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
–  Use the “Adaption” function to match any remote control units to the supplementary heater control unit -J364- → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
–  Interrogate the event recorder of the auxiliary heater control unit -J364- and erase any faults displayed → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
–  Interrogate the adaption of the supplementary heater control unit -J364- and if necessary alter the adaption in the “Pipe filling” adaption channel (metering pump -V54- actuation time for pipe filling) and perform basic setting in the “Pipe filling” display group (to erase the “Pipe filling” fault) → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
–  Start the engine and interrogate the event recorder of all the control units fitted. Faults may also have been entered for other control units by way of the data bus → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
–  Switch on the auxiliary heater and check operation of the auxiliary heater as well as the CO2 content of the exhaust gas → Chapter.
–  After replacing certain auxiliary heater components, switch on the auxiliary heater and allow it to run for at least 10 minutes in full load mode before handing over the vehicle to the customer. There may still be remnants of factory lubricant for example in the components and these would evaporate following initial activation as soon as the components become hot.
t  Removing auxiliary heater → Chapter
t  Installing auxiliary heater → Chapter.
t  Bleeding coolant circuit → Chapter.
  A82-0419

Removing auxiliary heater > < Removing and installing heater coolant shut-off valve N279