HWH Corporation
(On I-80, Exit 267 South)
2096 Moscow Road
Moscow, Iowa 52760

Phone: (563)724-3396 or (800)321-3494
Fax: (563)724-3408

Business Hours: 8 a.m. - 5 p.m. Central Time (M-F)

The World's Largest Manufacturer
of RV Leveling & Room Extension Systems
Electronics and HWH

CHAPTER 1. Preface.

CHAPTER 2. Electrical components.

  • 2-1 Manual control switches.
    • 2-1.1 Manual switch diagnostics
  • 2-2 Electric coils.
  • 2-3 Relays.
    • 2-3.1 Relay diagnostics
  • 2-4 Fuses.
  • 2-5 Diodes.
  • 2-6 Transistors.
  • 2-7 Control boxes and panels.
    • 2-7.1 Control box or panel diagnostics.
  • 2-8 Warning switches.
    • 2-8.1 Kick-down style jacks
    • 2-8.2 Straight-acting or fixed style jack warning switches
      • 2-8.2.1 The side port switch
      • 2-8.2.2 The 2 inch plunger switch
      • 2-8.2.3 The two wire magnetic warning switch
    • 2-8.3 One and two wire warning switch diagnostics
      • 2-8.3.1 If a jack is retracted and the warning indicators will not go out.
      • 2-8.3.2 If a kick-down jack is vertical or a straight-acting jack has extended and the warning indicators are not on
    • 2-8.4 Three wire warning switches
      • 2-8.4.1 Three wire warning switch diagnostics
  • 2-9 Pressure switches.
    • 2-9.1 Jack pressure switch
    • 2-9.2 3000 psi hydraulic manifold pressure switch
    • 2-9.3 50 psi hydraulic manifold pressure switch
    • 2-9.4 5000 psi hydraulic synchronizing cylinder pressure switch
    • 2-9.5 Air compressor air pressure switch
    • 2-9.6 Air bag air pressure switch
    • 2-9.7 System air pressure switch
    • 2-9.8 Pressure switch diagnostics
  • 2-10 Limit switches.
    • 2-10.1 Limit switch diagnostics
  • 2-11 Solenoid valves-hydraulic and air.
    • 2-11.1 Air solenoid valves
    • 2-11.2 Hydraulic solenoid valves
    • 2-11.3 Solenoid valve diagnostics
  • 2-12 Pump motors.
    • 2-12.1 Pump motor diagnostics
  • 2-13 Level sensing units.
    • 2-13.1 Level sensing unit adjustments
    • 2-13.2 Level sensing unit programming
    • 2-13.3 Level sensing unit diagnostics
  • 2-14 Electrical connectors and wire terminals.
    • 2-14.1 Common types of connectors and terminals used by HWH
      • 2-14.1.1 Deutsch connectors
      • 2-14.1.2 Packard Weather Pack connectors
      • 2-14.1.3 UML (Universal Mate-N-Lock) connectors
      • 2-14.1.4 MTA (Mass Termination Assembly) connectors
      • 2-14.1.5 EJS connectors (Econoseal J series by AMP)
      • 2-14.1.6 Solderless crimp-on terminals and quick disconnects

CHAPTER 3. Electrical test and repair equipment. Basic functions and use.

  • 3-1 Test lights.
    • 3-1.1 Selecting a test light
  • 3-2 Digital multimeters, Voltmeter, Etc.
    • 3-2.1 Selection of a meter
    • 3-2.2 Digital multimeter functions
    • 3-2.3 Reading the digital multimeter
    • 3-2.4 Using the multimeter
  • 3-3 Other test and repair equipment
    • 3-3.1 Clamp-on amp meter
    • 3-3.2 Wire strippers
    • 3-3.3 Test leads
    • 3-3.4 Soldering equipment

TEST