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Revision B December 2013
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Troubleshooting Guide
Safety Notes
Warning:
Always wear eye protection when working on or around machinery or
power tools and while working with hydraulics.
Warning:
Do not attempt to control a hydraulic leak with your hand. High-
pressure hydraulic fluid can puncture the skin and cause severe injury or death.
Use extreme caution when working on hydraulic systems.
In general, consult Energy Absorption Systems Customer Service Department if problems
associated with operating or repairing the TMA should arise. This guide is meant to be an aid for
performing minor repairs, not a detailed repair manual.
Note:
For any problems not listed here, contact Energy Absorption Systems.
Test Equipment for DC Powered Hydraulic Systems
The following is a recommended list of the test equipment required to troubleshoot DC powered
hydraulic systems.
1. Pressure
Gage
A small 34,450
KPa
[0-5000 psi] pressure gage, preferably glycerin filled, is a valuable
and relatively inexpensive tool for checking pressure in the various sections of the
circuit.
2.
DC Test Light
A test light is a light bulb with one lead wired to an alligator clip and the other lead
connected to a metal probe. It is used to check for the presence of a voltage in the
electrical circuit. With the alligator clip grounded, the light glows when the probe comes
into contact with a “HOT” electrical component.
3. Continuity
Light
The continuity light is a test light which contains its own battery.
It is used for testing
electrical circuits when the components are not connected to a power source.
4. Voltmeter
A DC voltmeter can be used to troubleshoot voltage problems. Two common uses are:
1) Ground one probe while using the other to probe hot leads in search of the available
voltage at the point where the second probe is connected. 2) Measure a voltage drop in
a wire or component by connecting one probe to one end and the remaining probe to the
other end of the item in question.
5. Ohmmeter
Note:
All tests conducted with an ohmmeter must be done with the power source
disconnected from the system.
An ohmmeter is used to measure resistance and is useful when working with solenoid
coils. On some coils the wire resistance is large enough that a DC test light might not
illuminate, falsely indicating an open circuit (infinite resistance). A successful coil test,
however, should always show some non-infinite value of resistance.
