CHARLOTTE, N.C. – Charlotte-Mecklenburg Schools announced Thursday that the investigation of a second school bus that caught fire remains active.

In a press release, CMS said the manufacturer of Bus No. 188, Thomas Built, has provided a third-party investigator to join the investigation. As soon as the results from the bus’s inspection are available, CMS said their findings will be made public.

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An investigation into the cause of a fire on Bus No. 164 on October 19 was inconclusive. CMS Transportation Services provided an update on October 23 to all technicians to ensure a thorough mechanical inspection of all buses that utilize the Freightliner 3126 engine.

In that update, it was determined that wires connected to the starter motor may have shorted out on the bus’s frame or a bracket holding them, or that the starter motor itself suffered a catastrophic failure.

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As part of the further inspection of all buses with 3126 engines, technicians are advised to inspect the rubber sleeves protecting the wires and to replace or repair them as necessary. These instructions were shared with officials at the North Carolina Department of Instruction Transportation Division.

CMS officials said that all 250 buses in their fleet with the Freightliner 3126 engine and Thomas Built chassis have been inspected with no areas of concern found.