Difference between revisions of "Headlight Condensation"

Revision as of 10:50, 19 January 2009

Headlights may suffer from condensation. Some types of condensation are covered by warranty and others not. See the below TSB for details.

Technical Service Bulletin No.LA417-002V3 15 February 2005

This bulletin supersedes TSB LA417-002V2/2005 dated 17 January, which should either be destroyed or clearly marked to show it is no longer valid (e.g. with a line across the page).

Subject/Concern : Discovery 3/LR3 - Headlamp Internal Condensation

Models : Discovery 3 / LR3 Markets : All

Summary :

This bulletin provides information on standards relating to acceptable/unacceptable levels of condensation that may occur in Discovery 3/LR3 headlamps.

This bulletin has been re-issued for revised part numbers.

Cause : The misting is generally caused by natural condensation and can be expected under certain atmospheric conditions. Certain levels of condensation are deemed acceptable by Land Rover. NOTE : Incorrect replacement of bulb-covers following bulb replacement can lead to condensation forming. Ensure bulb-covers are correctly installed. If this is determined to be the cause of the condensation, measures should be taken to dry out the lamps and to ensure that the bulb-covers are installed correctly. Condensation levels should be monitored to allow natural dissipation of the condensation.

Action : Should a customer express concern relating to the above, this bulletin has been issued to assist service personnel in providing a detailed explanation relating to Land Rover's standards on this subject.

Service Procedure Normal condensation is a natural process. Discovery 3/LR3 headlamps are vented to alleviate changes in pressure through a sophisticated Gore-Tex vent. Atmospheric air contains water vapor referred to as humidity. When this air enters the headlamp under any circumstance, there is a possibility that condensation can occur if the temperature is cold enough. When normal condensation occurs, a thin film of mist can form on the inside surface of the plastic lens. The thin mist will clear and exit through the vents during normal operation.

During a period of normal headlamp operation the condensation should dissipate as the lamp heats up.

However, if considerable water droplets still remain on the inside of the headlamp glass (refer to attached illustrations), the lamp should be renewed. If there is evidence of standing water within the headlamp unit, the unit will also need to be renewed. For additional information, refer to Global Technical Reference (GTR) Discovery 3/LR3 Workshop Manual Section 417-01, Exterior Lighting - Headlamp Assembly (86.40.49).

NOTE : Headlamps with light misting should not be renewed under warranty. Please refer step 1 and step 2 for clarification of headlamp renewal which will be covered under warranty.

1 . For headlamp renewal covered by warranty please refer to the following attached illustrations: 1 . Large apparent visible droplets of water on the interior side of the clear plastic lens. Refer to attached illustration E58385 2 . Drip marks/streaks in the film of condensation on the interior side of the clear plastic lens. Refer to attached illustration E58386 3 . Thick mist covering a majority of the interior side of the clear plastic lens. The thick mist also obstructs the view of the interior of the lamp. Refer to attached illustration E58387 4 . Puddles/pools of water in the interior of the headlamp.

2 . For headlamp renewal NOT covered by warranty please refer to the following attached illustrations: 1 . No drip marks/streaks in the finely condensed film on the interior side of the clear plastic lens. Refer to attached illustration E58388 2 . There are no visible water droplets in the thin mist. Refer to attached illustration E58389 3 . The fine mist does not obstruct the view of the interior of the lamp. Refer to attached illustration E58390 4 . Condensation covers less than 50% of the interior side of the lens. Refer to attached illustration E58391 5 . Headlamps with no visible condensation.

Attached Illustration - E58385 Headlamp Condensation Covered by Warranty - 1 (Large water droplets)

Attached Illustration - E58386 Headlamp Condensation Covered by Warranty - 2 (Drip marks/streaks in condensation)

Attached Illustration - E58387 Headlamp Condensation Covered by Warranty - 3 (Thick mist covering the lens with water droplets)

Attached Illustration - E58388 Headlamp Condensation NOT Covered by Warranty - 1

Attached Illustration - E58389 Headlamp Condensation NOT Covered by Warranty - 2

Attached Illustration - E58390 Headlamp Condensation NOT Covered by Warranty - 3 (Mist does not obstruct the view of the lamp's interior)

Attached Illustration - E58391 Headlamp Condensation NOT Covered by Warranty - 4 (Fine mist covers less than 50% of the lens)

--DiscoStu 21:50, 18 January 2009 (UTC)DiscoStu