Statewide memo issued requiring bus inspections after CMS bus fires

1999 FS Chassis Freightliner Wiring Harness Fire Hazard and FS 65 battery Wire Rubbing Bolt Through Fire Wall

A statewide memo was sent out on Friday by the NC Department of Instruction Transportation Division requiring school bus inspections following the multiple CMS bus fires. 

The memo, titled DPI Meesage #879 Bus Fire Prevention, states there have been two recent fires on FS65 with CAT 3126 engines this school year. The source of those fires i still under investigation, but officials said they appear to have started in the engine compartment. 

Related: CMS announces 5-point response following recent school bus fires

The memo asks school districts to please review the following information:

  • In May 2011 - DPI Message # 539 - DPI informed all counties of the potential for fire in the engine compartment due to deteriorating wiring harness wire ties on Freightliner FS chassis. The high exhaust manifold temperatures allowed the alternator wire to fall on the manifold igniting the fire. DPI inspectors have still seen in some bus garages where they have not performed the repair to the valve cover wires as requested or needed additional repairs. Please ensure that these issues are addressed. 
  • 2. The expectation when performing a 30-Day Inspection is to inspect the wiring in the engine compartment for damage, chafing or exposed wires. (Page 46 of the NC BUS FLEET: North Carolina School.  Transportation Fleet Manual, North Carolina State Board of Education Policy TRAN-005).  When performing 30 day inspections technicians should also pay close attention to the battery wire showing signs of rubbing/chaffing from a bolt that goes through the fire wall on the FS65 chassis Freightliners. (see picture below, driver side wiring harness between engine and firewall.) 
  • 3.The NC Bus Fleet inspection manual stresses the importance of making repairs when oil or fluid leaks are discovered due to this being potential fuel to a fire in the event one occurs.   

The memo concludes with stating, "This message shall serve as a notice that every model year 1998-2003 school bus when a Caterpillar engines must be inspected again, and if needed, repaired. 

Charlotte-Mecklenburg Schools issued the following statement on Friday: 

"CMS takes any possibility of harm to students and staff seriously and has already been proactive in addressing areas of concern identified during investigations of bus #364 and bus #188.

As a part of those proactive efforts and as previously stated and shared on November 2, 2017, as a proactive measure, CMS is inspecting 250 school buses, activity buses and spare buses with similar engine types. These inspections are closely examining the wiring area of those buses, to determine if there is any indication of a failure.”