Abstract: A pivotal control housing for enabling service access to a hydraulic control circuit is provided which is particularly useful with multi-power source service vehicles and includes hinge structure for enabling pivoting of the housing between an upright orientation and a horizontal position for servicing. The housing includes an access opening in the rear and enables the circuit to be easily accessed and serviced on the vehicle. The housing advantageously includes a pivotally mounted abutment bar for preventing the simultaneous opening of two valves leading to a single output which would otherwise overload the output.