Volvo Car USA LLC

Technical Journal

Technical Journal Title

Ref. No.

Issuer (Dept.)

Issue Date

Headlamp Condensation - Information/Leak test
Technical Service
Car Market

TJ 34521.11.1
5/5/26

Partner

United States and Canada

Function Group

3 US 7510 Volvo Car USA

Function Description

Headlamp, complete

3521

Status Date

5/5/26

Page

Page 1 of 3

Rows beginning with * are modified
Note! If using a printed copy of this Technical Journal, first check for the latest online version.

DESCRIPTION:

*Updated vehicle type information.
If there is condensation, moisture or mist inside the headlamp lens, follow advice under “Service”.

CSC Customer Symptom Codes
Code
W4

Description

Headlights/Moisture/mist on inside of lens

DTC Diagnostic Trouble Codes
Vehicle Type
Type Eng
224

Eng
Desc

Sales

Body

Gear

Steer Model Year

-

201835-209952

2019-9999

-

201846-209952

2019-9999

234

2017-2017

235
236

238
246
256

356
416
417

536

539

Struc Week
Range

2019-9999

225
227

Plant Chassis range

2017-9999
2017-9999
2017-9999

2018-9999

2016-9999

2025-9999
2025-9999

2026-9999
2019-9999

2022-9999

-

201817-209952
201617-209952

201624-209952

201646-209952
201646-209952
201717-209952

201505-209952
202417-209952

202336-209952

202509-209952
201746-209952

202139-209952

Technical Journal 34521.11.1
SERVICE:

> General information regarding moisture in the headlamps
Condensation in headlamps
Although the headlamps are waterproof, it is natural and inevitable that a certain amount of
moisture can appear in the headlamps. The amount of moisture / condensation depends on the
climate in which the car is used and on what driving behavior the customer has.
•
•
•

In markets or times of the year with high relative humidity, there is greater risk of condensation
accumulating in the headlamp.
If the car is used rarely or mostly for shorter periods of time, the risk of condensation increases.
Fast and great temperature changes also increase the risk of condensation.

To avoid or eliminate moisture in the headlamps, use the car regularly with high or low beam
engaged. The car also needs to be used for a longer driving cycle, which corresponds to more than
approximately 30 minutes of driving. Having the light on, with the car standing still, for 30 minutes
can cause more moisture in the lamps.
If a car has condensation in the headlamps, it usually does not help to replace them with new
headlamps, as the moisture is likely to come back in the new lamps as well.
Note that the headlamps are designed to withstand moisture and that the functionality of the
lamp is not affected by condensation.

Why condensation occurs in headlamps
Ambient air and humidity will diffuse into the headlamp through the ventilation openings. When
there is a drop in temperature, this humidity might convert from gas into liquid form and may
be visible as a fine mist on the inside of the lamp lens. The higher the relative humidity of the air
is, the lower the temperature drop needs to be before the humidity condense into liquid. With
normal use, the moisture inside the headlamp will evaporate when the headlamp warms up and
ventilates back out into the ambient air outside. If the car is only used for shorter periods of time,
condensation inside the lamp will not have time to convert back to gas form. This means that
more and more humid air will enter the headlamp and convert to fluid form when air inside the
lamp cools down. If the car is used many times without the moisture having time to evaporate, the
condensation can accumulate, and the buildup may then be visibly perceived by the customer.
After a headlamp test with approved result
Inform the customers that the headlamp with condensation is acceptable since the lamp have has
passed the leakage test. Condensation should disappear when the car is used
for longer intervals.

Page 2 of 3

2026-05-05

Technical Journal 34521.11.1
Condensation
Condensation is a natural phenomenon that sometimes occurs in the headlamps of a car. It occurs
more often during certain conditions, including:
•
•
•

If the car is used in markets or times of the year with high relative humidity.
If the car is used in short intervals, driving cycle shorter than 30 minutes.
If the car / headlamps are exposed to high and rapid temperature changes (e.g. when washing a
car during the summer).

To prevent or eliminate condensation in the headlamps, the car must be used regularly and for a
sufficient amount of time to allow the moisture in the lamps to dry up.
If a headlamp passes the leak test, it does not help to replace it.
> Fault tracing:

If the condensation/moisture/mist does not disappear despite fulfilling above criteria’s, follow
below steps:
1.

Check the headlamp assembly, lens, seals and ventilation holes/membrane for cracks or
damages.
2. Perform a leak test according to repair in VIDA, Information=> Repair => Cleaning, inspection
and adjustment => 3 Electrical system => 35 Lighting => 352 lighting, front => Headlamp
leak test
3-a. If the result is not ok (air leak), it is ok to replace the headlamp. Add leak test result in the
“repair order text” field, add video/photos of the symptom and the possible leakage location
in a Vehicle report.
3-b. If the test is ok (no air leak), then the headlamp shall not be replaced.

Warranty claim info:

To get a warranty claim accepted for a job described in this TJ, use the corresponding VST OP
number stated in this TJ.
Please note that fault tracing is not eligible for separate reimbursement under this TJ. Any fault
tracing VST operation numbers will be rejected.
Note, that the TJ number must be stated in the repair order text.

VST Operation Number

VST Operation Number Description
98810-2

98802-2

Removal, replacement and installation x1
Headlamp leak test x1

VEHICLE REPORT:

Yes, please submit a Vehicle Report if the service solution described in this TJ has no effect. Use
concern area “Vehicle Report” and sub concern area “Support Not Needed”, use function group
3521.

2026-05-05

Page 3 of 3