This bulletin announces a design change to the brake light switch (BLS) to reduce the possibility
of improper illumination of the ABS and/or VDC warning lamp. In the event a product containing
silicone is used to lubricate the BLS or for other purposes in the area around the switch, a non-conductive
coating may develop over time on the internal electrical contacts and affect operation of the
switch. On / Off signal output from the BLS is critical for proper operation of various systems on the
vehicle. When the switch does not operate properly, warning lamps illuminate and DTCs are stored.
A table with BLS-related DTCs and additional information is provided in the Service Procedure
information. A photo of the switch changes is shown below. This bulletin also provides a
diagnostic and adjustment procedure to be used when diagnosing brake light switch-related DTCs.
