Lighting - One Xenon Headlamp Flickers Or Is Inoperative

94 Xenon headlight flickers or is inoperative on one side (DTC 00978 or 00979)

94 10 19

2021751/3

June 7, 2010

Supersedes Technical Service Bulletin Group 94 number 10-10 dated April 29, 2010 for reasons listed below.





Affected Vehicles





Condition

^ The Xenon headlight on one side of the vehicle flickers or is inoperative (intermittently or permanently).

^ One of the following DTCs is stored in the Electronic Central Electronics control module J519 (address word 09) for the affected headlight:

^ DTC 00978 (Left Low Beam Headlight -M29- Electrical fault in circuit).

^ DTC 00979 (Right Low Beam Headlight -M31- Electrical fault in circuit).

^ The Xenon bulbs were manufactured by Philips.

Technical Background

Only Philips-brand Xenon bulbs are affected.





The Xenon bulb may have an internal leak at the crimp of the electrodes. If this occurs, the Xenon gas can be released.

Without an adequate amount of Xenon gas, the bulb cannot establish a stable light arch. The Xenon igniter control unit repeatedly tries to establish the arch, which may cause a flickering of the headlight.

Production Solution

Improved Xenon bulbs beginning on June 1, 2008.

Service

If the condition occurs intermittently:

1. Locate the 4-digit alphanumeric date code on the label of each of the Xenon bulbs.





2. Use the date code and the decoder table below to decipher the production dates.





^ If the Xenon bulbs were produced before June 1, 2008 (date code F801):

^ Replace both bulbs, even without a customer complaint. The bulbs will be covered under LNVW.

^ If the Xenon bulbs were produced after June 1, 2008 (date code F801):

^ Replace only the affected bulb. The bulb will be covered under LNVW.

If the condition occurs permanently:

Swap the bulbs between the left and right headlights.

^ If the complaint follows the bulb:

Replace the bulb(s) according to the production date as described in the intermittent condition diagnosis above. (Reference the decoder table below to decipher date code.) The bulb will be covered under LNVW.

^ If the complaint does not follow the bulb:

Check the power supply and control unit of the headlight assembly according to Guided Fault Finding.








Warranty

Tip: If both Xenon bulbs were replaced at the same time due to this TSB, only one Warranty claim must be submitted per vehicle.

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.