On a small number of trucks, the methane detection system may have been wired incorrectly. As a result, the detection system won't warn the driver if it loses power. This could allow a methane gas buildup to go undetected.
Safety Risk
A methane detection system that does not work could increase the risk of fire or injury.
Corrective Actions
PACCAR will notify owners by mail and instruct you to take your truck to a dealer to rewire the warning alarm and light for the methane detection system.