SAAB WIS ONLINE

(TA351-0809) Fogging/condensation in the headlamps

TECHNICAL ADVICE - Quick information for your help
Bulletin Nbr: TA351-0809
Date: ........... March 2008
Market: All
Fogging/condensation in the headlamps

VEHICLES CONCERNED

Saab 9-3 M08 within the following Vehicle Identification Number ranges:

4D/5D: 81000001 - 81126848

CV: 86000001 - 86007706

BACKGROUND

Market complaints of fogging/condensation in the headlamps.

CONDITIONS

This kind of condensation is an effect of normal air humidity. A more complete explanation can be found in "Aid for Argumentation" on page 3.

Saab will not accept any claims on replacement due to fogging/condensation.

SYMPTOM DESCRIPTION

Visible condensation on the inside of the clear lens.

In case of customer complaint, the following items have to be checked/replaced to avoid unnecessary replacement of headlamps.

ACTION


Items to check:

• Covers on rear part of headlamp correctly fitted

• Headlamp without any cracks and visible damage


It should be noted when discussing the matter with customers that the time for the dissipation process for condensation is extremely dependent on weather conditions such as temperature, humidity and the driving conditions. The condensation will disappear faster when driving long distance compared to city traffic.

To improve the ventilation of the headlamp:

Install the new improved ventilation hose 12 843 636


1. Remove the old ventilation hose

2. Install the new hose according to the picture below.

Note : It is not necessary to remove the headlamp to install the new vent hose.



Aid for Argumentation

The following description may be used as an aid to explain the situation for the customers. The headlamp is equipped with a ventilation system that is needed for releasing over pressure caused by the bulb heating up the interior of the lamp.

This interior heating creates a temperature difference between in / outside of the lens and moisture will condensate on the inside. In the presence of high humidity and high temperature differences between the inside and the environment, condensation will occur on the inside of the lens, especially in cold times of the year and in damp weather. Condensation can occur, for example, after using a car wash, steam cleaning the engine and the front of the vehicle, if temperature changes occur during the night, etc.

Even the smallest imaginable moisture in the air inside the headlamp can be precipitated on the lens, especially in the "subsequent heating phase", during which the back of the headlamp is heated because the engine is still warm, but at the same time the lens is being cooled down by cold outside air. Since lenses with a clear appearance are now being used, which may also be tinted, this phenomenon is more obvious than on lenses with a structure.

Fogging/condensation is also more visible in modern styled headlamps without chromed parts inside. The process involved in condensation in headlamps is caused by physics and does not affect the optical function of the headlamp (light output) in any way.

Neither can the condensation cause any corrosion in the headlamp. The phenomenon of condensation can occur on any headlamp, including our competitor vehicles, because it is caused by a physical process.

Replacing the headlamp is therefore unacceptable because no technical defect within the meaning of the warranty is involved.