30967-0150 Tohatsu GROMMET A, MOTOR COVER

Electrical System Ground Requirements
Proper grounding for vessel and engine electrical systems is necessary for proper performance and reliability.
Improper grounding will cause uncontrolled and unreliable circuit paths.This can result in damage to the engine's crankshaft main bearings, crankshaft journal surfaces or other engine components, and can cause electrical activity which may degrade the vessel's electronics and electrical communication equipment.
Starting Motor and Alternator
The engine's starting motor MUST be grounded directly to (-)Battery post. The alternator and ALL electrical systems MUST be grounded to (-)Battery Bus Bar. The alternator and starting motor MUST meet marine society isolation requirements.For engines which have the alternator grounded to an engine component, the component MUST be electrically isolated from the engine and a ground strap MUST connect that component to (-)Battery Bus Bar. If equipped with an alternator ground plate, the ground plate should have a direct path to (-)Battery Bus Bar (common ground point).The wire size from a ground plate MUST be of adequate size to handle full alternator charging current.Electrical Power Supply Connections to ECM
Starting Motor, Alternator, Voltmeter, Ignition Switch(es) and Engine Shutdown Switch
All (-)Battery connections must have a common ground that terminates at the (-)Battery Bus Bar. Refer to Electrical System Ground Requirements in this guide.
Power Supply Connections to Start (Ignition) Switch(es)/Engine Starting Motor
1. Connect (+)Battery, using 14 AWG wire, to the (+) terminal of the Start (Ignition) Switch.2. Connect the RUN terminal of the Start (Ignition) Switch, using 14 AWG wire, to Pin-6 of J1 Customer Connector.3. Connect (-)Battery, using 14 AWG wire, to Pin-5 of J1 Customer Connector.4. Connect (+)Battery, using 14 AWG wire with an in line 5A fuse, to Pin-4 of J1 Customer Connector. The ECM and CMS/EMS MUST be powered from the same ignition switch. The same battery source must be used for all (+)Battery and (-)Battery connections.Vessels may be equipped with an engine protection shutdown system (external to ECM) that interrupts electrical power to the ECM. These systems will not supply power to the ECM until the engine is cranked, until oil pressure achieves minimum acceptable limits or until an override button is pressed.These devices must not interrupt the Unswitched (+)Battery line. Current draw from the ECM through the Unswitched (+)Battery line is less than 10 milli-amps (0.01 amps) and will not cause a battery to discharge unless the engine is unused for months. Example: If a PORT battery supply and a STBD battery supply are used, then all connections to the PORT engine must be to the PORT battery supply. All connections to the STBD engine must be to the STBD battery supply. All battery supplies should be connected to a battery back up system. 5. Connect the START terminal of the Start (Ignition) Switch, using 14 AWG wire, to Starting Motor (Pinion Solenoid) Start terminal.6. Connect (+)Battery post directly to the (+) terminal on starting motor using the appropriate diameter (AWG) wire for the distance between connections.7. Connect (-)Battery post directly to the negative terminal on starting motor using the appropriate diameter (AWG) wire for the distance between connections.Recommended Wire from Battery to Starting Motor.
* Use 0 AWG up to 2.5 m (8.20 ft).* Use 00 AWG up to 3.25 m (10.66 ft).* Use 000 AWG up to 4.0 m (13.12 ft).* Use 0000 AWG up to 5.0 m (16.40 ft).Engine Shutdown Connection
Turn the Start (Ignition) Switch to the OFF position. This will interrupt the power supply to the ECM causing the engine to shutdown.Alternate Method For Engine Shutdown
Engine Shutdown Switch Schematic.1. Connect (-)Battery Bus Bar to the switch common of a (N/O) switch.2. Connect the N/O terminal to Pin-14 (Shutdown Input) of J1 Customer Connector or ... to Pin-3 of Caterpillar supplied engine shutdown solenoid. Use of this type switch and system is the preferred method of shutting down the engine.