During inspections of 2021 Green Power School Buses by California Highway Patrol (CHP) Motor Carrier Specialist (MCS) personnel at the Hughson Union School District (HUSD), it was discovered brake tubing is blown out of push-to-connect fitting(s) at a brake valve (under the bus) during a full brake application, causing a complete loss of brake system air in just a minute or two. An HUSD mechanic told the CHP MCS conducting the inspection that they have had the issue before and believed it was likely a bad fitting. The HUSD mechanic cut the brake tubing, reinstalled it into the fitting and the repair held during a subsequent brake application. However, after closer inspection of the tubing the MCS discovered the tubing, installed by the manufacturer, does not bear any of the marking identifying it as air brake tubing, required by California law contained in Title 13, California Code of Regulations, Section 1254(i)(2). The tubing in question appears to be unreinforced nylon and was found to be installed on three other Green Power school buses at HUSD. The HUSD mechanic also indicated they were aware that another school in Oroville CA has experienced this issue with Green Power school buses, however, the CHP has not yet confirmed the HUSD mechanic's statement. At this time, exactly how many Green Power school buses are in use, and equipped with non-airbrake tubing in the brake system in CA, is unknown. However, since the issue is an apparently resultant from a manufacturer defect the CHP requests NHTSA investigate the concern. The attached files show the tubing in use, the valve where the issue occurred and the piece of the tubing cut off as a result of the failure.

Source: NHTSA complaint ODI #11474107 · view all complaints for this vehicle at nhtsa.gov