Standard Control Module (Scm) - Toro 30344 Operator's Manual

Standard Control Module
(SCM)
The Standard Control Module is a potted electronic device
produced in a one 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 monitors inputs including 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 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
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 the On position 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 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.
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.
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, 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 34
34