Ernest Azoadam, of Flores Island, near Tofino, could not be revived and died in hospital Feb. 15.
- Father demands answers about teen party bus death
Coroner Vincent Stancato said it's not clear what led to the teenager's death.
"There were certainly low levels of both alcohol and cannabis in his system, but neither would suffice to explain his death," he said.
Originally, alcohol and drugs were believed to have caused Azoadam's death, which spurred calls for stronger oversight for the party bus industry.
The coroner's investigation into the cause of the death is continuing.