Tail Lamp - Excessive/Abnormal Condensation
File In Section: 10 - BodyBulletin No.: 53-15-19
Date: December, 1995
Subject:
Excessive or Abnormal Condensation in the Rear Taillamp Assemblies (Replace Taillamp)
Models:
1992-96 Cadillac Seville
This bulletin cancels and supersedes Corporate Bulletin Number 111521.
Previous divisional publication numbers were:
Cadillac 93-I-11
GM of Canada 93-10-147
Condition
Some vehicles may exhibit excessive or abnormal condensation in the rear taillamp assemblies.
Cause
It is important to understand the difference between "normal" and "abnormal" condensation:
Normal Condensation
Occurs when the air inside the lamp reaches the dew point and condenses on the lens as a fine mist or fog. Completely sealed lamps are not used on most vehicles. GM exterior lamps are of a vented design. They are designed to remove any excess moisture by expelling it through a vent system. The vent system functions at all times but functions most effectively when the vehicle is moving (air flows through the lamp), or if the lamp is turned on. Normal condensation should clear within 24 hours in a stable, dry atmosphere.
Abnormal Condensation is
^ Numerous droplets of water on the inside surface of the lens, or if any water droplets have condensed and run down the lens.
^ The area of mist/fogging exceeds one-half of the surface area of the lens.
^ An accumulation of water in bottom of the lens.
Correction
If abnormal condensation is present, replace the affected taillamp with one of the following described below.
When replacing taillamps on vehicles with a four point mounting system, it is necessary to install a rubber plug and new taillamp retaining nuts. The rubber plug will be used to plug a hole, marked "A" in Figures 1 and 2, previously used for taillamp mounting and the new retaining nuts represent the new thread design which match the replacement taillamps.
Parts Information
When replacing taillamps on 1992 vehicles, it is also necessary to replace the taillamp wiring harness for each lamp replaced.
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty.