Toro 30343 Operator's Manual page 29

The module is divided into inputs and outputs. Inputs
and outputs are identified by yellow 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 a LED that is illuminated when
the specific circuit is energized. Use the input LED's
for switch and input circuit troubleshooting.
Output circuits are energized by an appropriate set of
input conditions. The three outputs include PTO, ETR,
and START. Output LED's monitor relay condition
indicating the presence of voltage at one of three
specific output terminals.
1. Inputs
2. Backlap
3. High temperature shutdown 7. Parking brake Off
4. High temperature warning
Here are the logical troubleshooting steps for the SCM
device.
1. Determine the output fault you are trying to resolve
(PTO, START, or ETR).
2. Move key switch to "ON" and ensure the red
"power" LED is illuminated.
3. Move all input switches to ensure all LED's change
state (Seat, Brake, Traction Pedal, PTO and Start.
4. Position input devices at appropriate position to
achieve the appropriate output. Use the following
Note: Each row (across) in the logic chart below identifies input and output requirements for each specific product
function. Product functions are listed in the left column. Symbols identify specific circuit condition including:
energized to voltage, closed to ground, and open to ground.
5. In seat
6. Power Take-off (PTO)
8. Neutral
Output circuits do not determine output device integrity
so electrical troubleshooting includes output LED
inspection and conventional device and wire harness
integrity testing. Measure disconnected component
impedance, through wire harness (disconnect at
SCM), or by temporarily "test energizing" the specific
component.
The SCM does not connect to an external computer or
hand held device, can not be re–programmed, and does
not record intermittent fault troubleshooting data.
The decal on the SCM only includes symbols. Three
LED output symbols are shown in the output box. All
other LED's are inputs. The chart below identifies the
symbols.
Figure 28
9. Outputs
10. Power Take-off (PTO)
11. Start
12. Energize to Run (ETR)
logic chart to determine the appropriate input
condition.
5. If specific output LED is illuminated without
appropriate output function, check output harness,
connections, and component. Repair as required.
6. If specific output LED is not illuminated, check
both fuses.
7. If specific output LED is not illuminated and inputs
are in appropriate condition, install new SCM and
determine if fault disappears.
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13. Start
14. Power