Two scenarios exist that cause trucks to catch fire – one is during or resulting from a crash, and the other is when a truck is left unattended. ARCCA experts have investigated many of these incidents. In the crash situation, the cause is often found to be diesel that ignited when it splashed on a hot surface or came in contact with a positive electric cable that goes to ground.
In the other scenario, the truck is left unattended for an extended period of time and, when the driver returns to the truck, he finds it has burned. In one such case, we inspected the truck and found that the diode, which is internal to the alternator, had deteriorated to the point that it was unable to manage the power. As a result, the alternator caught fire, thereby causing the entire truck to catch fire.