Toro Reelmaster 3100-D Operator's Manual page 57

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.
Each row (across) in the logic chart that follows identifies input and output 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 In
ON Neutral
—
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 continuity of the disconnected device, and
the potential voltage on the ground circuit (floating ground). Repairs will vary depending on your findings.
Start Brake
ON ON
—
+
O
—
O O
—
O O
—
O O
—
O O
O
PTO ON In Seat Hi Temp
—
O O
O O O
—
O O
— —
O
—
O O
—
57
OUTPUTS
Backlap Start ETR
+ +
O
+
O O
+
O O
+
O O
—
+
O
O O
PTO
O
O
O
+
+
O