Principles Of Operation; Safety Interlock System; Checking Out The System; Model Variation Notes - Simplicity Broadmotor Series Service & Repair Manual

• OFF grounds the engine ignition coil through the igni-
tion switch, preventing ignition system sparking. The
safety interlock module can also ground the ignition
coil through the #5 and #4 terminals.

Principles of Operation

IGNITION SHUTDOWN SYSTEM
When the ignition switch is in the "START" or "RUN" posi-
tion, the ignition circuit is open, allowing the engine to
run.
When the ignition switch is turned to "OFF," the engine is
shut off by grounding the ignition coil.
CHARGING SYSTEM
While the engine is running, current flows from the alter-
nator to the positive battery post and charges the battery.
CRANKING SYSTEM
The cranking system is composed of the ignition switch,
the safety interlock switches, the PTO switch, the
solenoid, and the interlock module.
Cranking system current path:
1. Current travels from the battery through the circuit
breaker, through the ignition switch, through the sole-
noid, through the safety switches to the interlock mod-
ule. A second wire connects the solenoid to the #1
post of the inter lock module. If the safety switches
are closed, the module grounds the solenoid, cranking
the starter.

Safety Interlock System

The safety system is controlled by the interlock module.
The safety switches are used to trigger the module.
Operator Present Sub-System
The operator present sub-system is designed to protect
the operator from injury if the operator would leave the
seat.
1. Engine should shut off when the operator rises
off the seat if ANY of the following conditions
exist:
A. Brake pedal is not depressed.
B. PTO clutch switch is engaged.
2. Engine should remain on when the operator rises
off the seat ONLY if ALL of the following condi-
tions are met:
A. Brake pedal is fully depressed (or parking brake
set).
B. Electric clutch switch disengaged.
7 Electrical System Service
Safety Starting Sub-System
The safety starting sub-system will prevent the engine
from cranking if any of the following conditions exist.
1. Engine should NOT crank if ANY of the following
conditions exist:
A. PTO clutch switch is engaged.
B. Brake pedal is not depressed.
C. The operator is out of the seat.
2. Engine should crank ONLY if ALL of the following
conditions are met:
A. Electric clutch switch disengaged.
B. Brake pedal is fully depressed (or parking
brake set).
C. The operator is in the seat.

Checking Out the System

BASIC ELECTRICAL TERMS
"Ground" is the negative battery post or any other con-
ductive part of the frame. For best results, use the nega-
tive battery post as ground.
"VOM" is a volt-ohm meter, multi-meter, or equivalent.
"VDC" is volts of direct current or the VOM setting used
to measure DC voltage.
"Ohm" is units of resistance or the VOM setting used to
measure resistance.
"Continuity" is a continuous, unbroken circuit. In this
manual continuity is determined with a VOM set to mea-
sure ohm. Zero ohm is true continuity. However, due to
contact point corrosion and resistance within wires, conti-
nuity may measure a few ohm.
"No Continuity" is a broken circuit. In this manual no
continuity is determined with a VOM set to measure
ohm. No continuity will register as infinite ohm.
"Battery Voltage" is the approximate voltage output of
the battery. Keep in mind that "battery voltage" tested at
any component will be slightly lower than "battery voltage"
tested at the battery terminals due to resistance within
connections and wires.

Model Variation Notes

WIRE HARNESSES & IGNITION SWITCHES
Several different wiring harnesses and ignition switches
have been used in the foot-controlled Broadmoor Series:
early models used a two-piece main harness, later mod-
els used a one piece main harness, six pin and five pin
ignition switches have both been used (see appropriate
parts manual for specific information).
HOWEVER, all Broadmoor / 1600 / 2600 series electrical
systems use the same interlock module and function the
same.
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General Information