Kohler COMMAND CH18, Service Manual

Page: 73 / 232

5B.4
Section 5B
EFI Fuel System
Important Service Notes!
• Cleanliness is essential and must be maintained
at all times when servicing or working on the EFI
system. Dirt, even in small quantities, can cause
significant problems.
• Clean any joint or fitting with parts cleaning
solvent before opening to prevent dirt from
entering the system.
• Always depressurize the fuel system through the
test valve in fuel rail before disconnecting or
servicing any fuel system components. See fuel
warning on page 5B.2.
• Never attempt to service any fuel system
component while engine is running or ignition
switch is ‘‘on.’’
• Do not use compressed air if the system is open.
Cover any parts removed and wrap any open
joints with plastic if they will remain open for
any length of time. New parts should be removed
from their protective packaging just prior to
installation.
• Avoid direct water or spray contact with system
components.
• Do not disconnect or reconnect the wiring
harness connector to the control unit or any
individual components with the ignition ‘‘on.’’
This can send a damaging voltage spike through
the ECU.
• Do not allow the battery cables to touch opposing
terminals. When connecting battery cables attach
the positive (+) cable to positive (+) battery
terminal first, followed by negative (-) cable to
negative (-) battery terminal.
• Never start the engine when the cables are loose
or poorly connected to the battery terminals.
• Never disconnect battery while engine is running.
• Never use a quick battery charger to start the
engine.
• Do not charge battery with key switch ‘‘on.’’
• Always disconnect negative (-) battery cable lead
before charging battery, and also unplug harness
from ECU before performing any welding on
equipment.
Electrical Components
Electronic Control Unit (ECU)
Figure 5B-1. “35 Pin” (MA 1.7) Metal-Cased ECU.
Figure 5B-2. “24 Pin” (MSE 1.0) Plastic-Cased ECU.
Figure 5B-3. “32 Pin” (MSE 1.1) Plastic-Cased ECU.