TEST - LESSON 13 – PART 3
HYDRAULIC LEVELING SYSTEM IDENTIFICATION AND OPERATION – AUTOMATIC LEVELING SYSTEMS
THE 625, 625S AND 725 SERIES
1. What is the most reliable way to identify a specific leveling system?
______
2. What are 2 similarities between the 610 series systems and the 625 series systems?
1. ______
2. _______
3. What are 2 major differences between the 610 series systems and 625 series systems?
1. ______
2. _______
4. Each jack has two valves, one extends the jack and one retracts the jack. True ___ False ___
5. What does the shuttle valve do? ________
______
6. Is the shuttle valve activated electrically or with hydraulic pressure? ______
7. The pump is running. When one jack is on the ground under pressure and that valve is opened along with the valve for a jack that is not under pressure, what will happen if there are no inner and outer check valves in the hydraulic manifold? ______
8. How many wires are in the harness that connect the touch panel to the control box? ________
9. What is the value of the terminating resistor used at each end of the twisted pair of wires in the touch panel cable?
A. 60 ohms
B. 90 ohms
C. 120 ohms
D. 240 ohms_______
10. Where are the terminating resistors located for the 625 leveling systems?
______
11. How many buttons are there on a 625 touch panel for a system with air dump? _________
12. How many lights are there on a 625 touch panel for a system with air dump? ___________
13. How many lights are there on a 625 touch panel for a system without air dump? ________
14. Put an X beside the LEDs that are on the 625 control box main PC board. Hint: You will probably have to refer to the HWH website to get this correct.
_____ 50 psi pressure switch _____ 3000 psi pressure switch _____ Shuttle valve
_____ Left front output _____ Left side level light _____ Master relay output
15.Each output relay in the 625 control box has a yellow and red LED. The yellow LED for the right front jack output is on but not the red. What does that mean and what could the problem be?
______
______
16. Which output relay on the 625 pc board is wired with normally closed contacts?
________
17. What “direction” do we label the passenger side of the vehicle? (U.S. vehicles) _________
18. What two things do the programming jumpers on the level sensing unit determine?
1. _________
2. _________
19. What is the main objective of the Series-Parallel operation?
______
20. The system has kick-down style jacks. The jacks kick down to the vertical position in a specific order. Number the jacks in the correct order.
Right rear jack _____
Left front jack _____
Left rear jack _____
Right front jack _____
21. When leveling the vehicle, manually or automatically, there are two parts. First we level the vehicle then stabilize the vehicle. When we stabilize, we are making sure all 4 jacks are on the ground. What is an important thing that should happen during a stabilize procedure and why.
________
______
______
22. In the automatic stabilizing procedure, what is the difference between how the front jacks and rear jacks are stabilized?
________
______
______
23. What is the main difference between the 625 and 625S systems?
______
______
______
24. You want to stop a 625S automatic leveling or store procedure. Put an X beside the button(S) that can be pushed to stop an automatic procedure.
____ Left front UP arrow button ____ AUTO LEVEL button ____ DUMP button
____ CANCEL button ____ Left front DOWN arrow button ____ AUTO STORE button
25. Briefly explain the operation of a single step 625S system with kick-down style jacks.
________
26. What is a new feature became available with the 725 system?
____________
27. What is the same about the 625 and 725 leveling systems with kick-down jacks?
________
28. The basic hydraulic functions for a 725 system are the same as the 625 systems.
True _____False _____
29. The front of the 725 touch panel (straight-acting jacks) looks the same as the 625S touch panel. There is a notable difference between the panels when the system is performing an automatic leveling or store procedure. What is that difference?
____________
30. Which component makes the decisions for the 725 systems? ___ MIOM ___ Touch Panel
31. Where are the terminating resistors for the 725 systems? ________
32.How many LEDs does a basic 725 MIOM have? _______
33. How is the level sensing unit different between the 625 style systems and the 725 systems?
________
______
34. The top of the sensing unit has an arrow. This arrow points to the _________ of the vehicle.
35. The leveling procedure for the 725 system is pretty much the same as the 625S leveling systems but the stabilize portion of the procedure is different. Briefly describe the difference.
______
______
______
______
Bonus Questions:
1. What valve does the main hydraulic manifold on the pump have for a system with the HWH cascading step system that the basic 725 leveling system manifold does not have?
______________
2. What two HWH lessons should be studied before taking Lesson 13, Part 3?
______
3. The 625 and 625S systems had a series-parallel operation that was used to protect the valves from overheating during the automatic store procedure. Explain what happens during a 725 system automatic store procedure if one red jack down warning light does not go out.
______
______
______
C:\1_Shawn\Fred\ml57000-023-test.doc | Revised: 08MAR18 | Page 1 of 5