1) Switch inputs indicate shuttle lever is in both forward and neutral 2) Switch inputs indicate shuttle lever is in both reverse and neutral 3) Switch inputs indicate shuttle lever is in both forward and reverse. Cycle the shuttle lever which may free up stuck switches, or try driving the opposite direction.
Challenger tractor depreciation is the allocation of cost of an asset among the time periods when the asset is used. For example, the cost of a machine that is used to produce products during several production periods should be distributed among those production periods. Depreciation is the concept for allocating that cost.