new speed sensor truck won't start?

[Nilao]

Check the clutch switch...just unplug it and jumper it. If it starts, replace switch. If not you could have a faulty starter relay. Peterbilt uses a ignition relay as well as a starter relay. My friend had this issue so i had him swap the ignition and starter relays.

Truck would then turn over but not start...a new relay fixed his issue.