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Revision B June 2013
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2 DC
Motors
Before concluding that the hydraulic pump is malfunctioning:
Verify that all connections are secure and that the problem does not lie somewhere
else.
Check
ground.
Check brushes for wear, and replace if necessary.
Note:
A motor that does not turn in freezing weather could be caused by frozen
water in the oil.
If it has been verified that the pump is defective; contact Energy Absorption Systems
Customer Service Department for input as to your specific application (See Page 3).
3 Electrical
Switches
A. If you suspect that the switch is defective, use one of these three methods to test the
operation of the switch:
1) First check grounds.
2) Use continuity light to test the switch (See Test Equipment section).
3) Use a circuit test light to test the switch (See Test Equipment section).
B. Motor solenoid switches:
The solenoid switches found on the hydraulic pump are four post style solenoid. They
shall be constructed and wired such that:
1) The large posts with the connecting bar must be attached to the cable from the
battery.
2) The same post (shared hot lead) provides power to the control circuit.
3) The remaining large posts attach to the motor wires.
4) The small post on each solenoid connects to the control circuit on the side and the
other small post connects to the ground. This circuit activates the solenoid (and
hence the pump) when energized.
4 Electrical
Polarity
The pump motor and all controls have a negative ground.
5 Electrical
Shorts
or Open Circuits
A. Shorts occur when wires with power come in contact with a ground. A short will cause a
fuse to blow or a wire to burn. Look for pinched or cut wires.
B. An open circuit is simply a break which prohibits current flow. Look for pinched or cut
wires.
