Scrub System182Service Manual – Advance 7765 / Nilfisk CR1500The Scrub Brush Solenoid (6), ScrubBrush Solenoid (8) and Scrub BrushLock Up Solenoid (9) are part of theCylinder Control Valve located belowthe access panel on the floor of theOperator compartment.The hydraulic hose from Port C1on the Cylinder Control Valve isconnected to the lower port on thescrub deck cylinder.The hydraulic hose from Port C2on the Cylinder Control Valve isconnected to the upper port on thescrub deck cylinder.TroubleshootingProblem Cause CorrectionScrub deck motorsnot running.No voltage to the NormalRotation Brush (4) solenoidin the Main Control Valve.1. Check circuit breaker CB7 and reset if necessary.2. Check that the Drive Pedal Forward Relay issending 12 VDC to the Forward Relay coil whenthe drive pedal is moved to the forward position.3. Check the continuity through the Forward Relayand Scrub Brush Switch to the Normal RotationBrush (4) solenoid. Repair the wiring, or replacethe relay and/or switch as necessary.Normal Rotation Brush (4)solenoid in the Main ControlValve not operating (stuckopen).1. Check the coil resistance of the Normal RotationBrush (4) solenoid. If not 7.2 ohms ±10%, replacethe coil.2. If the coil resistance is within spec, check forbinding or a mechanical problem. Repair orreplace the valve as necessary.Unable to changescrub brush rotationdirection.No voltage to the ReverseRotation Brush (3) solenoidin the Main Control Valve.1. Check circuit breaker CB7 and reset if necessary.2. Check the continuity through the Brush RotationSwitch to the Reverse Rotation Brush (3)solenoid. Repair the wiring or replace the switchas necessary.Reverse Rotation Brush (3)solenoid in the Main ControlValve not operating.1. Check the coil resistance of the Reverse RotationBrush (3) solenoid. If not 7.2 ohms ±10%, replacethe coil.2. If the coil resistance is within spec, check forbinding or a mechanical problem. Repair orreplace the valve as necessary.CylinderControl ValveManifold BlockScrub BrushSolenoid (6) Scrub BrushSolenoid (8)Scrub BrushLock UpSolenoid (9)Port C1 toBottom Porton Scrub DeckHydraulic CylinderPort C2 toTop Porton Scrub DeckHydraulicCylinder
