Installation Manual

Electrical & Electronic Application And Installation Manual
Production Release Version 1.0
Page 124
installation of a starting and charging system please refer to Tier 4F Starting
and Charging System A&I Manual.
10.2 Stopping the Engine (and Preventing Restart)
There is often some confusion about the different methods and devices used
to either stop the engine or to prevent it from starting. These devices may be
divided into the following categories:
• Ignition Keyswitch
• Battery Isolation Switch
• Remote Stop Button
• Datalink stop
• Engine Air Shutoff
Each of these devices is described below to assist the OEM in selecting the
method that is most suitable for machine and market. It remains, however, the
responsibility of the OEM to ensure compliance of the machine with any
specific legislation for the territories into which it is sold.
It is recommended that the OEM perform a risk assessment such as a Failure
Mode Effects Analysis (FMEA) on the application to determine the most
appropriate method of stopping the engine and/or preventing it from being
restarted.
Note: Cutting all electrical power from the engine whilst it is running will result
in an uncontrolled shutdown of the high pressure fuel system. Uncontrolled
fuel system shutdowns are likely to compromise the reliability of the high
pressure fuel pump. Therefore the methods detailed below are the only
recommended ways of stopping the engine.
It should be noted that under certain circumstances the engine ECM will
remain active i.e. electrically active post ignition key power off. This is
required for a number of engine calibration activities to take place. For this
reason the main ECM supply power (un-switched battery) must not be
removed during normal engine stopping. Removing the ECM un-switched
battery supply will cause these calibrations to be interrupted and the values
measured on the previous key cycle will be used. If the engine ECM is
operated for long periods without performing these calibrations, engine
performance may be affected and a diagnostic will be raised. During this
period the engine ECM will also require a certain level of current from the
system batteries for a short period of time. For this reason care must be
taken when working on the engine post ignition key off.
10.2.1 Ignition Keyswitch
It is a Perkins requirement that all machines have a simple intuitive and
accessible method of stopping the engine. This will normally be a directly
wired Ignition Keyswitch. When the keyswitch is turned to the off position or
when the key is removed, power must be removed from the ignition keyswitch
pin (pin 69) of the ECM J1 connector. Switching devices may also be placed