Condition

Customer states:

Workshop findings:

The Following DTC may be stored relating to the Comfort System Central Control Module, -J393- (address word 0046):

The ignition button is working correctly.

 

This TSB only applies in conjunction with the event memory entry AND symptom number 65638.

Technical Background

The DTCB143C29Access/Start Authorization Button, implausible signal” withsymptom number65638means that not all the positions of the button were detected when it was pressed 30 times in a row (from model year 2023: 50 times). The reason may be that the customer did not press the button all the way down.

Production Solution

From model year 2023: Threshold at which the event memory entry is logged increased to 50 presses.

Service

 

In convenience system central control unit J393 (diagnostic address 0046), please check whether all three button positions are detected in the measured value “entry and start authorization button” when the button is pressed all the way down.

Important: Audi does not use contact 4. An operation is never shown here when the button is pressed. Contact 4 must not be included in the analysis.

If the DTC is logged statically and all button positions were detected, it should subsequently be intermittent.

If all button positions are detected, it can be assumed that the button is okay and that the complaint was caused by the button not being fully pressed down several times in a row. It is not necessary to replace the button.

Please inform the customer accordingly:

Please press the “START ENGINE STOP” button all the way down, as otherwise the message “Power unit start system: fault. Please contact workshop” or “Engine start system: fault. Please contact workshop” will be shown on the instrument cluster if the button is not pressed all the way down 30 times in a row (from model year 2023).

Warranty

All warranty claims submitted for payment must be in accordance with theAudi Warranty Policies and Procedures Manual. Claims are subject to review or audit by Audi Warranty.

Additional Information

All part and service references provided in this TSB (2077631) are subject to change and/or removal. Always check with your Parts Department and/or ETKA for the latest information and parts bulletins. Please check the Repair Manual for fasteners, bolts, nuts, and screws that require replacement during the repair.

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