MEC升降车平台94047-SCH-A92-20维修电气原理图手册

Section 19-TroubleshootingJuly 2021General Troubleshooting TipsHydraulic Fluid PumpThe hydraulic Drive Pump and Primary Functions Pump used in this model are variable displacement,axial piston type pumps.Proper adjustment is critical for normal operation of the machine.Refer toSection 10 of this manual.The Secondary Functions pump is a fixed-displacement gear-type pump attached to the rear of thePrimary Functions Pump.Common Causes of Electrical System Malfunctions:Battery switch is turned OFF (located at the front of the engine module).Battery connections are loose or corrodedBattery is not fully charged.Emergency Stop buttons are pushed (OFF position).Circuit breaker is tripped (OFF position).Common Causes of Hydraulic System Malfunctions:Hydraulic fluid level is too low.Incompatible hydraulic fluids mixed,destroying the additives and causing vamish build up,resulting in the valves sticking.Water in the hydraulic fluid due to a damp climate.Improper hydraulic fluid used.Viscosity too high in cold climates.Viscosity too low in warmclimates.Hydraulic fluid contaminated with debris-filter change interval neglected.Note:MEC uses a multiple viscosity fluid that is light enough for cold climates and resists thinning inwarm climates.Use only the recommended hydraulic fluid.Substituting a lower grade fluid willcause the machine to operate incorrectly and may lead to pump and drive motor failure.Referto "Lubrication"in Section 10 of this manual.Note:Contamination always causes failure in any hydraulic system.It is very important to be carefulnot to introduce any contamination into hydraulic system during the assembly procedures.Make sure all ports and cavities of the manifold and cylinders are properly covered/pluggedduring maintenance activities.Page 9560-J Diesel-Service Parts Manual(mec)