An assembly includes an inlet tube. The assembly includes a first outlet tube. The assembly includes a solenoid assembly having a plunger movable between an open position in which fluid is permitted to flow from the inlet tube to the outlet tube and a closed position in which fluid is inhibited from flowing from the inlet tube to the outlet tube. The solenoid assembly has a spring urging the plunger to the closed position. The solenoid assembly has a strain gage fixed to the spring. A strain detected by the strain gage indicates whether the plunger is at the closed position.