Hydraulic Solenoid Diagnostic

Technical Support Subject Hydraulic Solenoid Testing Version Document Department Revision Details Author Reviewed by Implemented Tech. Eng. C EXT-PRED-017 Tech Additional solenoids BDJ RB N/A 27 Sept 2022 Page 1 of 5 Knowledge Base: http://kb.vmacair.com/ Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Sales:1(800)738-8622 Fax: 1(877)740-3201 SYSTEM OR PARTS AFFECTED • VMAC 40cfm and 60cfm Hydraulic Air Compressors • A700280 40cfm and 60cfm Hydraulic Air Compressor Cold Climate Kit • A700190 and A700191 CLOSED CENTER MANIFOLD KIT for 40cfm and 60cfm (respectively) • 9400155 ASSY, HYD, LOAD SENSE MANIFOLD INDEX System or Parts affected .................................................................................................................................... 1 Index..................................................................................................................................................................... 1 Overview .............................................................................................................................................................. 1 Testing ................................................................................................................................................................. 1 Hydraulic solenoid valve in 9400048 manifold................................................................................................. 1 Hydraulic solenoid valve in A700280 Cold Climate Kit .................................................................................... 3 Hydraulic solenoid in A700190 and A700191 Closed Center Manifold Kit ...................................................... 4 Hydraulic solenoid in 9400155 Hydraulic Load Sense Manifold Assembly ..................................................... 5 OVERVIEW Hydraulic solenoid valves electrically open and close hydraulic pathways, closing them off or changing the direction of flow. In VMAC Hydraulic Driven compressor systems, these hydraulic solenoid valves can be used to: • Direct flow to the hydraulic motor to drive the air compressor. • Cause oil to flow through specific hydraulic circuits to warm the hydraulic oil when required. • Change flow characteristics to achieve desired behaviour from the hydraulic pump. (Closed center and load sense) If diagnostics indicate that there may be a problem with a hydraulic solenoid, testing of the solenoid should be performed. If a solenoid coil fails testing, the coil and the poppet valve should be changed together. TESTING HYDRAULIC SOLENOID VALVE IN 9400048 MANIFOLDS OF ALL 40CFM AND 60 CFM HYDRAULIC AIR COMPRESSORS (Figure 1). This hydraulic solenoid valve is normally open and is “ground switched” by the control box (voltage is always present but until the control box provides a ground there is no circuit). This creates a closed loop through the Hydraulic Manifold to warm the hydraulic fluid. Once the hydraulic fluid has warmed sufficiently the control box switches a ground to close the solenoid redirecting fluid flow through the hydraulic motor. Technical Support Subject Hydraulic Solenoid Testing Version Document Department Revision Details Author Reviewed by Implemented Tech. Eng. C EXT-PRED-017 Tech Additional solenoids BDJ RB N/A 27 Sept 2022 Page 2 of 5 Knowledge Base: http://kb.vmacair.com/ Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Sales:1(800)738-8622 Fax: 1(877)740-3201 Check resistance of the solenoid coil:  Disconnect the hydraulic solenoid connector.  Using a multimeter, check the resistance value through the Part number 4500130 Solenoid Coil.  Correct resistance range = 7.2Ω to 8.8Ω The manual solenoid actuation process is intended for testing only. Once you have confirmed that the solenoid opens and allows hydraulic fluid to circulate to the motor disconnect the solenoid from the battery to close the Solenoid. Manually activate the solenoid valve:  Start the truck and turn on the hydraulics.  Ensure that the Hydraulic Drive Air Compressor is turned “On” at the display box.  Disconnect the solenoid coil connector.  Apply +12V and ground to the solenoid coil from an external source such as the battery.  Listen for the hydraulic motor and the compressor to start.  If the air compressor does not start, then both the Solenoid Poppet Valve (P/N# 4500129) and the Solenoid Coil (P/N# 4500130) need to be replaced. Measure the voltage coming from the control box connector by grounding one probe and measuring voltage with the other on each of the red wires. There should be 12VDC on each wire.  If there is no voltage or less than 12VDC check wires for continuity.  If the wires have good continuity replace the Control Box. Figure 1 Solenoid coil P/N# 4500130 Solenoid poppet valve P/N# 4500129 Technical Support Subject Hydraulic Solenoid Testing Version Document Department Revision Details Author Reviewed by Implemented Tech. Eng. C EXT-PRED-017 Tech Additional solenoids BDJ RB N/A 27 Sept 2022 Page 3 of 5 Knowledge Base: http://kb.vmacair.com/ Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Sales:1(800)738-8622 Fax: 1(877)740-3201 HYDRAULIC SOLENOID VALVE IN A700280 COLD CLIMATE KIT (Figure 2). This hydraulic solenoid valve is normally open and is “ground switched” by the control box (voltage is always present, but until the control box provides a ground there is no circuit). Check resistance of the solenoid coil:  Disconnect the hydraulic solenoid connector  Using a multimeter, check the resistance value through the part number 3551039 Solenoid Coil.  Correct resistance = approximately 5.2Ω Figure 2 Solenoid poppet valve P/N# 4500157 Solenoid coil P/N# 3551039 Technical Support Subject Hydraulic Solenoid Testing Version Document Department Revision Details Author Reviewed by Implemented Tech. Eng. C EXT-PRED-017 Tech Additional solenoids BDJ RB N/A 27 Sept 2022 Page 4 of 5 Knowledge Base: http://kb.vmacair.com/ Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Sales:1(800)738-8622 Fax: 1(877)740-3201 HYDRAULIC SOLENOID IN A700190 AND A700191 CLOSED CENTER MANIFOLD KIT FOR 40CFM AND 60CFM (RESPECTIVELY) (Figure 3). This hydraulic solenoid valve is normally closed and is “ground switched” by the control box (voltage is always present, but until the control box provides a ground there is no circuit). Check resistance of the solenoid coil:  Disconnect the hydraulic solenoid connector.  Using a multimeter, check the resistance value through the part number 4500138 Solenoid Coil.  Correct resistance = approximately 7.2Ω Figure 3 Solenoid poppet valve P/N# 4500137 Solenoid coil P/N# 4500138 Technical Support Subject Hydraulic Solenoid Testing Version Document Department Revision Details Author Reviewed by Implemented Tech. Eng. C EXT-PRED-017 Tech Additional solenoids BDJ RB N/A 27 Sept 2022 Page 5 of 5 Knowledge Base: http://kb.vmacair.com/ Email: tech@vmacair.com Web: www.vmacair.com Technical Support: 1(888)241-2289 Sales:1(800)738-8622 Fax: 1(877)740-3201 HYDRAULIC SOLENOID IN 9400155 HYDRAULIC LOAD SENSE MANIFOLD ASSEMBLY (Figure 4). This hydraulic solenoid valve is normally closed and is “ground switched” by the control box (voltage is always present, but until the control box provides a ground there is no circuit). Check resistance of the solenoid coil:  Disconnect the hydraulic solenoid connector.  Using a multimeter, check the resistance value through the part number 4500168 Solenoid Coil.  Correct resistance = approximately 6.2Ω Figure 4 Solenoid coil P/N# 4500168 Solenoid poppet valve P/N# 4500167