Lighting - LED Daytime Running Lamp Diagnostic Tips
94 LED Daytime Running Light Diagnosis Tips94 12 96
2027773/3
November 1, 2012.
Supersedes Technical Service Bulletin Group 94 number 12-69 dated March 15, 2012 for reasons listed below.
Affected Vehicles
Condition
Part or all of the daytime running lights do not work on vehicles with LED DRLs.
For vehicles with halogen DRLs, please reference TSB 2017488, 94 Halogen Daytime running lights do not work.
Technical Background
In the past, the daytime running light bulbs were a serviceable part. In this application, the LED strip cannot be replaced, and may have an associated control module. This TSB is for servicing information only.
Production Solution
Not Applicable.
Service
1. If a DTC is listed in J519 related to daytime running lights, follow the respective test plan before proceeding with this bulletin.
2. If both front DRLs are inoperative, verify the DRLs are turned on via the vehicle system option:
^ A3, TT, R8:
The daytime running lights are automatically switched on when the headlight switch is set to AUTO. If the headlight switch is set to OFF, the DRLs will be off. This functionality cannot be changed.
^ A4 (8K), A5, A6, A7, A8, Audi Q7:
In vehicles with MMI, the daytime running lights are switched on via the menu option Exterior light control or Exterior Lighting.
See also the owner's manual of the respective vehicle types.
3. If one or several LEDs are not illuminated (Figure 1), the affected headlight assembly must be replaced. The LED light strip is not a serviceable item.
Tip: Only the headlight assembly needs to be replaced. Any headlight control modules can be reused.
4. If all DRL LEDs in one headlight assembly are inoperative, there are typically two possible causes:
^ LED circuit board.
^ DRL control unit, located inside the headlight assembly.
Tip: For 2009 - 2010 Audi Q5 vehicles, please follow TSB 2020780, 94 One or more Daytime Running Light LEDs in one headlight assembly are inoperative.
A3, A5 (2008-2012), and TT vehicles do not have serviceable DRL control units, as these modules are integrated into the headlight. On these vehicles, the entire headlight assembly must be replaced.
For other vehicles, in order to verify the root cause, swap the DRL control units between the two headlights.
^ If the problem is no longer present, leave the control units on the currently installed side, and release the vehicle. Manufacturing differences between components can sometimes lead to concerns that can be remedied simply by exchanging right and left control modules.
^ If the problem follows the suspect DRL control unit, replace the DRL control unit.
^ If the problem does not follow and remains on the original side, verify all headlight connections, and replace the headlight with the inoperative LED.
Warranty
This TSB is informational only and not applicable to any Audi 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.
More diagnostic assistance on this system can be found in the following resources:
^ All Models: TSB 2023322, 94 Different color shades in LED daytime running lights
^ 2010 - 2011 Audi Q7: TSB 2022410, 94 Right daytime running light is inoperative in Coming Home mode (DTC 02746/007)
^ 2009 - 2010 A6: TSB 2023287, 94 LED daytime driving light inoperative on one side