This article provides information regarding condensation related to the accumulated moisture in the headlamp, rear tail lights, daytime running lamp (DRL), or fog lamp.
In this article we illustrate the various causes of condensation inside the lamp assembly. Lamp assembly replacement is NOT necessary in most cases. This condition can be eliminated by turning on the lamps with the engine running for several minutes or during normal driving operation
The amount and location of condensation will vary based on environmental factors and vehicle usage conditions (lamp usage, driving time and/or distance, etc.).
Condensation may occur on only one side of the vehicle if it is parked in a certain position that exposes one side to direct sunlight while the other side is in shade.
A similar example of the natural occurrence of condensation is windshield fogging. During cold temperatures, the warm air inside the cabin may condense on the windshield if it has enough moisture.
This occurs because the warm air is cooled down past its dew point as it flows over the cold windshield surface. The dew point is the temperature at which the air is unable to “hold” any more water vapor. The water vapor in the air will begin to condense into liquid droplets (dew) if the air is cooled down past its dew point.
Condensation from the accumulated moisture is a normal occurrence. Lamp assembly replacement is NOT necessary to resolve this condition.
1. Normal Condensation
Condensation occurring inside the lamp assembly after rain or a car wash cycle is considered a natural occurrence. Condensation can also occur after the vehicle is parked outside during cold temperatures. This condition occurs when water vapor inside the lamp assembly is exposed to temperature variations. This condensation is NORMAL and replacement is NOT REQUIRED.
2. Water Leak
If water is collecting at the bottom of the lamp assembly, water streaks are present, or the condensation remains after the lamps have been on for 30 minutes or more, there may be a water leak in the assembly. The leak may be caused by a poor seal between the lamp housing and lens, cracks in the lamp assembly, or poor fitment. The condition should be diagnosed and repaired as necessary.
Lamp Assembly Drying Guidelines
• Ensure that the vehicle is parked in a well-ventilated area and that the dust cap(s) have been removed prior to drying the lamp assembly.
• Certain lamp assemblies may have two dust caps. Remove both dust caps if applicable.
• To avoid battery discharge, the engine must be running while the lamps are on. • Allow the vehicle to idle for 30 minutes with the engine running and lamps turned on for the condensation and moisture to evaporate.
• Reinstall the dust cap(s) after drying the lamp assembly.
• If condensation still remains, replace the lamp desiccant or moisture absorbent pack, if equipped, and repeat the lamp assembly drying procedure again
