Front Seat And Neck Heating
Front seat heating is available as optional equipment on the Audi TT. For more information. Refer to the Owner's Manual and Front Seat Covers and Cushions . Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-). Refer to the appropriate Wiring Diagram.
Neck heating is only available on the Audi TT Roadster as optional equipment for seat heating. For more information about neck heating. Refer to the Owner's Manual and Front Seat Covers and Cushions . Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-). Refer to the appropriate Wiring Diagram.
Vehicles with optional "seat heating" equipment can be identified by the symbol -4- on the control heads installed in the left and right vents -1 and 2-.
There are different versions and part numbers for the Front A/C Display Control Head 1 -E774- -1- (installed on left) and for the Front A/C Display Control Head 5 -E778- -2- (installed on the right). Different data signals on the "LIN Bus" data wire from the Climatronic Control Module -J255- are used for allocating the signal for seat heating activation (and/or neck heating) from the Front A/C Display Control Head 1 -E774- for the left seat and the signal from the Front A/C Display Control Head 5 -E778- for the right seat. For problems with seat heating activation (and/or neck heating) on identical or interchanged control heads, use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Climatronic Control Module -J255-). Refer to the Parts Information and the appropriate Wiring Diagram.
Vehicles with optional "seat and neck heating" equipment can be identified by the symbol -3- on the control heads installed in the left and right vents -1 and 2-.
Vehicles with optional "seat and neck heating" equipment can be identified, for example, by the vent -A- that is installed in the seat. Refer to Front Seats .
Rear seat heating is not available on the Audi TT. Refer to Rear Seat Covers and Cushions and the appropriate Wiring Diagram. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-).
Components Involved in Activation of Seat Heating (and Neck Heating):
- The Front A/C Display Control Head 1 -E774- -1- sends the selected setting for the seat heating (and/or neck heating) for the left seat via a "LIN Bus" data wire to the Climatronic Control Module -J255-. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding"
function (for the Climatronic Control Module -J255-). Refer to the appropriate
Wiring Diagram.
- The Front A/C Display Control Head 5 -E778- -2- sends the selected setting for the seat heating (and/or neck heating) for the right seat via a "LIN Bus" data wire to the Climatronic Control Module -J255-. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Climatronic Control Module -J255-). Refer to the appropriate Wiring Diagram.
- The Climatronic Control Module -J255- -1- reports the selected setting for seat heating (and/or neck heating) for the left and/or right seat via a "LIN Bus" data wire to the Vehicle Electrical System Control Module -J519-. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding"
function (for the Climatronic Control Module -J255- and the Vehicle Electrical System Control Module -J519-). Refer to the appropriate
Wiring Diagram.
- The Vehicle Electrical System Control Module -J519- then directly activates the seat heating elements. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-). Refer to the appropriate Wiring Diagram.
- The Vehicle Electrical System Control Module -J519- then activates the Left Head Area Heater Control Module -J846- and/or the Right Head Area Heater Control Module -J847- via a data wire. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-). Refer to the appropriate Wiring Diagram.
- Check the function and activation of the seat heating (and/or neck heating) using the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Climatronic Control Module -J255- and the Vehicle Electrical System Control Module -J519-).
Procedure
The seat heating (and the neck heating) is adjusted using the control heads installed in the left and right instrument panel vents (Front A/C Display Control Head 1 -E774- -1- and Front A/C Display Control Head 5 -E778- -2-).
- When the seat heating (neck heating) is switched on, the function indicator lamps in the control heads -1 and 2- illuminate. Refer to the Owner's Manual.
- If it is not possible to switch on the seat heating (or neck heating) due to a shut-off condition detected by the Vehicle Electrical System Control Module -J519-, the Vehicle Electrical System Control Module -J519- sends the respective information back on the Data Bus (via the Climatronic Control Module -J255-) to the Front A/C Display Control Head 1 -E774- and/or the Front A/C Display Control Head 5 -E778- and the function indicator lamps in the control heads -1 and 2- do not illuminate or go out.
- The setting for the seat heating (and the neck heating) is adjusted on the control heads -1 and 2-. The specified temperatures for the various settings of the seat heating (and neck heating) are stored in the Vehicle Electrical System Control Module -J519-. Depending on the version of the Vehicle Electrical System Control Module -J519-, the specified temperature for seat heating may be different with the same setting on the control heads -1 and 2-. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function. Refer to the appropriate Wiring Diagram.
- The selected setting for seat heating (and neck heating) for the driver seat can be stored in the Climatronic Control Module -J255- in a key-dependent manner. The settings made prior to the ignition being switched off are applied during the next driving cycle. Refer to the Owner's Manual.
- Depending on the vehicle and the version of the Climatronic Control Module -J255- (or the Vehicle Electrical System Control Module -J519-), the selected setting for seat heating (and neck heating) may be automatically turned down a setting after running for a certain amount of time (for example, after 10 minutes). Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" . Refer to the Owner's Manual.
- For vehicles with the Start/Stop System, the seat heating (and neck heating) can be switched off to protect the Battery -A- when the Stop function is active. The setting for activating the seat heating (and neck heating) remains stored however in the Climatronic Control Module -J255-. Seat heating (and neck heating) is switched on again as soon as the engine is restarted via the Start function. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Vehicle Electrical System Control Module -J519-). Refer to the Owner's Manual.
- For vehicles without a passenger occupant detection system for the front passenger seat, the seat heating (and the neck heating) is not automatically switched off by the Climatronic Control Module -J255- or the Vehicle Electrical System Control Module -J519- at this time if a seat is unoccupied while driving. If the ignition is turned off and is not turned on again within approximately 10 minutes, the setting for activating the seat heating (and neck heating) on the front passenger side is erased. Refer to the Owner's Manual.
- If, for example, the Vehicle Electrical System Control Module -J519- voltage measured at terminal "30" falls below a value stored in the Vehicle Electrical System Control Module -J519-, the output of the seat heating (and neck heating) is reduced or switched off completely to reduce the load on the Generator -C-. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function for the Vehicle Electrical System Control Module -J519-.
- If there is a condition that prevents the driver or front passenger seat heating (or neck heating) from switching on (for example, there is a short circuit in the power supply to the particular control module, etc.), this will be stored as a fault in the Climatronic Control Module -J255- and in the Vehicle Electrical System Control Module -J519-. Information stating that the DTC memory in the relevant control module must be checked may not be sent via the Data Bus to the Climatronic Control Module -J255- control head on this vehicle. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Climatronic Control Module -J255- and the Vehicle Electrical System Control Module -J519-). In the event of a complaint regarding seat heating (or neck heating), first check the DTC memory of the control modules that can affect the activation.
- Depending on the version and vehicle equipment, the various information regarding the activation of the seat heating (neck heating), such as the setting transmitted by the Climatronic Control Module -J255-, the specified and actual temperature of the seat, etc. is displayed differently with different measured values in the various control modules. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function (for the Climatronic Control Module -J255- and the Vehicle Electrical System Control Module -J519-).
- In the "read measured values" function of the"Guided Fault Finding" for the Climatronic Control Module -J255-, it shows which setting for the seat heating (and neck heating) has been selected. The activation of the seat heating (and neck heating), the actual and target seat temperature, the actual current supplied to the seat heating (neck heating), etc. are displayed in the "Read measured values" function for the Vehicle Electrical System Control Module -J519-, depending on the vehicle version and equipment. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function.
- Function test description for the activation of the seat heating and neck heating. Use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function for the Vehicle Electrical System Control Module -J519-.
Seat Heating Function, Checking and Servicing. Refer to Front Seat Covers and Cushions and the appropriate Wiring Diagram.
For checking and servicing the function and activation of the neck heating, use the Vehicle Diagnostic Tester in the"Guided Fault Finding" function for the Vehicle Electrical System Control Module -J519-. Refer to Front Seats and the appropriate Wiring Diagram.