The vehicle a 51-year-old Berkeley man was driving crashed into a traffic signal pole at the intersection of Highway 29 and Madison Street in Yountville Monday.
The crash occurred at 12:40 p.m. and for a time closed the northbound lane of Highway 29.
The California Highway Patrol said Jeremy Pearson was driving northbound on the highway when his truck ran off the roadway and hit the signal pole head-on.
Pearson sustained major injuries and was taken to Queen of the Valley Medical Center, the CHP said.
The cause of the crash remains under investigation.
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