LI82.10-P-062051

Headlamps fogged
Topic number
LI82.10-P-062051
Version
9
Function group
82.10 Exterior lights
Date
06-30-2020
Validity
BR222 SA code 640 / 641 / 642 (dynamic LED headlamp)
BR205 SA code 640 / 641 / 642 (dynamic LED headlamp) before modification year 18/1
BR217 up to facelift
Reason for change
Validity adapted: BR205 before modification year 18/1
Reason for block
Complaint:
Lamp unit fogged or droplets forming.
Cause:
Because of the housing cover with pressure compensation membrane, the lamp unit is a “closed system”. This means
that the lamp unit is protected against acid gases, dirt and exhaust gas. However, moisture can still enter from two
sources.
Through absorption and desorption (the commonest cause) or through permeation.
Moisture is either absorbed by the plastic material and, when the light source is switched on, it is released from the
plastic by desorption, or the moisture penetrates through the plastic materials of the headlamp from outside (permeation).
This can lead to the formation of condensation on the lens of the headlamp.
Remedy:
Check housing cover of lamp unit for natural fogging or condensation as per LI82.10-P-050139.
.
1. If a reduction in the degree of fogging is visible, the desiccant packs can be used once the condensation has completely evaporated.
2. If no reduction in the degree of fogging is visible, the lamp unit is defective and must be replaced.
On the new lamp unit, the service cover with desiccant pack must be installed.
Since the replacement headlamps are not supplied with control units, use the control units from the headlamp with
condensation.
Make sure that the contacts of the old control unit are undamaged and dry.
.
Note:
Residual fogging is possible due to the laws of physics and is OK.
Fogging does not impair the functionality or the service life of the lamp unit.
Desiccant packs must always be used in both lamp units.
Install basket with desiccant pack and replace pressure compensation membrane.
.
1. Remove headlamp control unit [Figure 1].
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2. Fold desiccant pack carefully in the middle then place into basket and seal [picture 2].
Note: Two desiccant packs are required for each headlamp.
3. Place basket in headlamp [Figure 3] and reinstall control unit.
4.
The membrane already in the headlamp [picture 1] must be replaced by a new membrane (the membrane is
packed in the separate bag)
Note: The bonding surface must be clean and dry.
5.
If the headlamp housing has an additional 2nd membrane, this must be covered over with the masking tape.
Note: The bonding surface must be clean and dry.
.
To ensure that the drying pack (absorption) acts effectively, the headlamp has to be air-sealed.
Observe or check the following points for this:
1. The seals on the central connector must all be present [Picture 5 (1)] and correctly fitted [Picture 5 (2)].
2. The new transparent diaphragm must be correctly bonded [Picture 6].
3. Check headlamp housing for any external damage.
Note: Residual fogging is possible due to the laws of physics and is OK.
Fogging does not impair the functionality or the service life of the lamp unit.
Desiccant packs must always be used in both lamp units.
Attachments
File
Description
Bild 3.jpg
[ 1] Folding basket installed
Bild 1.jpg
Headlamp:
[ 1] Control unit
[ 2] Diaphragm
Bild 5.jpg
1) Seals missing
2) Seals not correctly fitted
Bild 6.jpg
Transparent diaphragm correctly or incorrectly bonded.
Bild 2.jpg
[ 1] Fold desiccant pack carefully in the middle.
[ 2] Place both desiccant packs carefully into basket.
[ 3] Seal folding lid
NOTE: Please make sure that the packaging is not damaged.
Symptoms
Lighting / Exterior lights / Driving lights / Main headlamps / Fogged
Parts
Part number
ES1 ES2 Designation
Quantity Note
EPC
A 000 826 13 00
LCU folding basket, right
1
X
A 000 826 12 00
LCU folding basket, left
1
X
Desiccant pack (15g)
2
2 desiccant packs per headlamp.
X
Masking tape
1
Masking tape for the existing 2nd
membrane (on headlamp housing)
X
A 000 826 16 00
09
A 000 826 20 00
Attachments
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Bild 5.jpg:
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