prime mover smx45 Master Service Manual page 164

F-code Section
PT S5.0
Electrical Functions
Version no T-code
002 SMX
162
Return
C-code
5000
Troubleshooting can be broken down into two sections: (1)
mechanical and (2) electrical circuits. Electrical circuits can
be further broken down into control circuit and power circuit.
Many hours of troubleshooting time can be saved by knowing
the exact operational symptoms. Check the control switches;
if they test as operating properly, the problem most likely will
be in the power circuit of that function.
The travel functions are controlled by the transistor controller.
Lift, lower, and horn functions operate separately. To use this
troubleshooting guide locate the failure symptom in the index
(see Troubleshooting Chart Index" on page
to the expanded outline, and follow the testing procedures
described.
Voltage tests are made with the negative lead of the volt
meter connected to battery negative. If the negative lead is
connected to a negative terminal on the electrical panel, first
verify the negative connection to the battery by touching the
positive meter lead to the positive battery post. The battery
voltage must be at least 25.2 volts for a 24 volt system. If
the battery voltage is below 22 volts (no load), then the
transistor controller may not operate properly. Charge the
battery before starting the troubleshooting procedures.
When testing voltage, the "POSITIVE SIDE" of any
component refers to the terminal on that component that is
closest electrically to the battery positive terminal. The
"NEGATIVE SIDE" of any component refers to the terminal
on that component that is farthest electrically from the battery
positive terminal. It is possible and in many cases desirable to
measure battery voltage on the negative side of a
component.
Forward direction refers to travel in the direction of the
control handle with the tractor-first. Reverse direction refers
to travel with the forks-first.
The parking brake will automatically engage when the truck
has come to a stop while the control handle is in the operating
range and no travel speed is requested. Normal stopping
during travel operation is obtained by reversing the travel
direction controls (plugging) or moving the control handle to
either the braking positions shown on
handle and the direction control operate together to release
the brake. The line contactor will be open when either of the
parking methods are applied.
Master Service Manual
188.) Then go
page 163. The control
2006-12-12