All Freightliner and Western Star vehicles, reverse light switch may not function when the vehicle is shifted into reverse

Applicable Vehicles:

All Freightliner and  Western Star vehicles that use the backup light switch P/N POL 21 465, POL 21 465P, POL 21 566 or POL 21 566PF  (typically manual transmissions) built up to March of 2019 can be affected. 

Symptoms:

Backup lights and if equipped with a backup alarm, may not function when the vehicle is shifted into reverse.

Issue:

The backup light harness routes on top of the transmission. Even though the backup light connector can connect to the backup light switch, the wire seals in the connector can be stressed due to wire length, not allowing the seals to properly seal.  Any moisture that may enter through the seal, can cause corrosion, resulting in a bad connection and or failure of the switch.

Solution:

To help eliminate any stress that may occur at the backup light switch connector, a jumper harness P/N A66-19642-000 has been created that provides additional length to the backup light harness. The jumper provides a new connector and wires that are blunt cut. To install the new jumper, just cut off the original backup light connector, and using two butt connectors P/N PHM 1 1862 attach the jumper.  Make sure that when reconnecting the connector at the backup light switch, that the wires are not stressed and enter the connector as straight as possible.  The attached picture shows an example of where the backup light switch is typically located on the transmission.