Keyless Starting - No Start/Battery Discharged
27 Battery discharged on vehicles with Advanced Key96 10 02
2019143/5
February 8, 2010.
Supersedes Technical Service Bulletin Group 96 number 09-15 dated November 20, 2009 for reasons listed below.
Affected Vehicles
Condition
^ The customer may report that the engine doesn't start due to a discharged vehicle battery.
^ Possibly affected vehicles must have the following equipment:
^ Audi Advanced Key (PR No. 4F2, 4K7 or 4I3).
^ Control unit for access and start authorization J518 (address 05) SW version below 240 (4F0 905 852 B) or below 50 (4F0 905 852 C).
Technical Background
Pressing the start button while the ignition key is not in the vehicle wakes the CAN comfort bus system and may keep the system awake. This may lead to a discharge of the vehicle battery to the point that an engine start is no longer possible.
Production Solution
New software in the control unit for access and start authorization (J518) resolved the problem.
Service
1. Connect the vehicle to an approved charger or voltage maintainer and verify the battery state of health with the "Battery Test Plan" in the 61 - energy management control unit J644. Recharge or replace the battery according to the result.
Tip: When replacing the battery, all necessary documentation must be attached to the work order.
2. Use the history data from the energy management control unit J644 (address 61) to verify whether an awake CANbus or customer influence (e.g. ignition or ext. lights on) has discharged the vehicle battery.
3. If an awake CANbus is confirmed, try to reproduce the condition.
a. Disconnect the battery charger/maintainer, if applicable.
b. Switch off ignition.
c. Remove all keys from the vehicle.
d. Press the start button and measure the closed-circuit current of the vehicle battery.
4. If the condition can be reproduced, perform a SVM software update of the control unit for access and start authorization J518 (address 05).
SVM Update Instructions
a. Follow the instruction in the attached TSB 2011732 00 Software Version Management (SVM), operating instructions.
b. Update the control unit for access and start authorization J518 (address 05) using SVM action code as listed in the table above if necessary.
Warranty
Additional Information
All parts and service references provided in this TSB are subject to change and/or removal. Always check with your Parts Department and service manuals for the latest information.