On some VOLVO VHD, VN, VT, and VAH truck models built between 04/31/2008 and 11/30/2015, the solenoid...

Bulletin number

FSB 593 012

Component

Electrical system: integrated trailer brake control

Summary

On some VOLVO VHD, VN, VT, and VAH truck models built between 04/31/2008 and 11/30/2015, the solenoid valve for the Hill Start Assist feature is prone to internal contamination in harsh environments. The internal contamination of the solenoid valve is caused by the buildup of grime, salt, road debris and other solid contaminants. In some cases, the buildup of solid contaminants caused the solenoid valve to malfunction. A similar malfunction is possible if the solenoid valve is equipped with a vent fitting that freezes over. The malfunction causes the trailer brake circuit to maintain trailer brake pressure after a grade Hill Start Assist event. Replacement of the existing solenoid valve, elbow, and the addition of a new tube fitting and tube will ensure proper functionality of the Hill Start Assist feature.

Owners of these vehicles have filed 2 complaints in the electrical category.