Troubleshooting The Standard Control Module (Scm) - Toro Reelmaster 3100-D Operator's Manual

Troubleshooting the Standard Control Module (SCM)

1. Determine the output fault you are trying to resolve (PTO, START, or ETR).
2. Move the key switch to the O
illuminated.
3. Move all the input switches to ensure that all LEDs change state.
4. Position the input devices at the appropriate position to achieve the appropriate output.
Use the following logic chart to determine the appropriate input condition.
5. If the specific output LED is illuminated without the appropriate output function, check
the output harness, connections, and component. Repair as needed.
6. If the specific output LED is not illuminated, check both fuses.
7. If the specific output LED is not illuminated and the inputs are in the appropriate
condition, install a new SCM and determine if the fault disappears.
Note:
requirements for each specific product function. The product functions are listed in the
left column. The symbols identify the specific circuit condition including energized to
voltage, closed to ground, and open to ground.
Logic Chart
INPUTS
Function Power
ON
Start —
Run (Off —
Unit)
Run (On —
Unit)
Mow —
Backlap —
Hi Temp —
• (–) Indicates a circuit closed to ground—LED ON.
• (O) Indicates a circuit open to ground or de-energized—LED OFF.
• (+) Indicates an energized circuit (clutch coil, solenoid, or start input)—LED ON.
• A blank indicates a circuit that is not involved with the logic.
To troubleshoot, turn on the key without starting the engine. Identify the specific function
that does not work and work across the logic chart. Inspect the condition of each input
LEDs to ensure that it matches the logic chart.
If the input LEDs are correct, check the output LED. If the output LED is illuminated but
the device is not energized, measure the available voltage at the output device, the
3466-297A
Each row (across) in the logic chart that follows identifies input and output
In Start Brake
Neu- ON ON
tral
— + O
— O O
O O —
O O —
— O O
O
position and ensure that the red power LED is
N
PTO In Hi
ON Seat Temp
O —
O O
O —
— —
— O
Page 8–2 Troubleshooting: Using the Standard Control Module (SCM)
Back- Start
lap
O O +
O O O
O O O
O O O
O — O
— O
OUTPUTS
ETR PTO
+ O
+ O
+ O
+ +
+ +
O O