Lighting - Xenon Headlamps Flicker On Vehicle Start up
94 Xenon light flickers at vehicle start94 10 37
2017083/3
September 27, 2010
Supersedes Technical Service Bulletin Group 94 number 08-33 dated November 13, 2008 for reasons listed below.
AFFECTED VEHICLES
CONDITION
This TSB only applies to 2008 A3, A4, and A4 Cabriolet models with bi-xenon headlights without cornering light. Xenon light flickers 25 seconds to 5 minutes (also described as flashing) immediately after starting the vehicle with the light switched on.
TECHNICAL BACKGROUND
During the vehicle start, the supply voltage of the xenon control unit drops under 6V for a few milliseconds. The voltage drop occurs when the light is started. As a result, clearly visible, low-frequency (in Hz range) pulsating of the light (flickering) may occur.
PRODUCTION SOLUTION
Optimized xenon control units.
SERVICE
1. Check whether the customer has the light switched on when starting the engine.
2. Check the specifications and the production date of the xenon control units.
^ Only 2008 model year vehicles with bi-xenon head lamps and without cornering light are affected. From production date 07.08.2007, the complaint no longer occurs.
3. If the customer has the light switched on when starting the engine and the vehicle is within the specified range, replace both xenon control units.
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.