01 volvo with cummins N14 celect plus

Question...i'm shutting down. The speedometer goes haywire, then I lose power, Then trucks on side of road. I wait for a few minutes, truck fires up. This is a intermittent problem. It can happen 4x daily or once daily. I did put it on computer came back with cam sensor fault + speedometer sensot. Replaced cam sensor. Still shuts down. I turn power on and check solenoid and theres no power to it. It seems like it cools down then starts. Anyone know could it be the solenoid? Does speed sensor shut truck off? Any ideas???

 

Thx baha. can I run a Hot wire rt from battery if I put and inline fuse in?