Standard-Control Module (Scm) - Toro Groundsmaster 3500-D Operator's Manual

Standard-Control Module
(SCM)
The Standard-Control Module (SCM) is a potted
electronic device produced in a 1-size-fits-all
configuration. The module uses solid state and
mechanical components to monitor and control
standard, electrical features required for safe product
operation.
The module-monitor input includes neutral, parking
brake, PTO, start, backlap, and high temperature.
The module energizes outputs including PTO, Starter,
and ETR (energize to run) solenoid.
The module is divided into inputs and outputs. Inputs
and outputs are identified by green LED indicators
mounted on the printed circuit board.
The start-circuit input is energized by 12 VDC. All
other inputs are energized when the circuit is closed
to ground. Each input has an LED that illuminates
when the specific circuit is energized. Use the input
LEDs for switch and input-circuit troubleshooting.
Output circuits are energized by an appropriate set of
input conditions. The 3 outputs include PTO, ETR,
and START. Output LEDs monitor the relay condition,
indicating the presence of voltage at 1 of 3 specific
output terminals.
Output circuits do not determine output-device
integrity, so electrical troubleshooting includes
output-LED inspection, conventional device,
and wire-harness-integrity testing. Measure the
disconnected-component impedance, impedance
through the wire harness (disconnect at SCM), or by
temporarily "test energizing" the specific component.
The SCM does not connect to an external computer or
handheld device, cannot be programmed again, and
does not record intermittent fault troubleshooting data.
The decal on the SCM includes only symbols. The
3 LED output symbols are shown in the output box,
while all other LEDs are inputs as shown in
1. Backlap (input)
2. High temperature (input)
3. In seat (input)
4. PTO switch (input)
5. Parking brake—off (input) 11. Power (input)
6. Neutral position (input)
Here are the logical troubleshooting steps for the
SCM device.
1. Determine the output fault that you are trying to
resolve (PTO, START, or ETR).
2. Move key switch to the O
that the red, power LED illuminates.
3. Move all of the input switches to ensure that all
LEDs change state.
4. Position the input devices at the appropriate
position to achieve the appropriate output.
Note:
the appropriate input condition.
5. Review the following repair options if a specific
output LED illuminates.
•
Figure 27.
•
•
29
Figure 27
7. PTO (output)
8. Start (output)
9. ETR (output)
10. Start (input)
N
Use the following logic chart to determine
If a specific output LED illuminates without
the appropriate output function, check
the output harness, connections, and
component.
Note:
Repair as required.
If a specific output LED does not illuminate,
check both fuses.
If a specific output LED does not illuminate
and the inputs are in the appropriate
condition, install a new SCM and determine
if the fault disappears.
g031611
position and ensure