1A-2 Engine Control System
E
ngine Control System
Precautions on Service
Circuit test tools
Unless otherwise specified in diagnostic procedures,
do not use Test Light to diagnose the powertrain
electrical system. When diagnostic procedures need
probe connector, use Connector Test Adapter Kit 5-
8840-0385-0.
On-market electrical equipment and vacuum
devices
On-market electrical equipment and vacuum devices
refer to those components that will be installed to
vehicles after shipment from manufacturing plants. Be
careful that installation of these components is not
considered during the process of vehicle design.
CAUTION:
Do not install on-market vacuum devices to
vehicles.
CAUTION:
Connect on-market electrical equipment, as well as
its power supplies and grounds, to the circuits
isolated from the electronic control system.
The on-market electrical equipment, even when
installed to vehicles in normal manner, may bring
functional troubles to the electronic control system.
Affected devices include those not connected to the
vehicle electrical equipment system, for example,
mobile phones or radios. Therefore, when you intend to
diagnose the powertrain, check such the on-market
electrical equipment has not been installed to the
vehicle and, if installed, remove it. If faults still occur
even after removal of on-market electrical equipment,
diagnose the vehicle according to normal procedures.
Damage by electrostatic discharge
Electronic components used in the electronic control
system are designed to work at very low voltages and,
for this reason, they are susceptible to damage by
electrostatic discharge and some types of electronic
components may be damaged even by the static
electricity of less than 100 V that is usually not sensed
by persons. Persons’ sensitivity level is 4,000 V.
Persons are electrostatically charged in various ways
and the most typical electrification sources are friction
and induction. Shown below are examples.
• Electrification by friction occurs when a person
slides on the seat in the vehicle.
• Electrification by induction occurs when a person
with insulating shoes is standing near a highly
electrifiable substance and touches a ground
momentarily. Electric charges with the same
polarity flow out and resultantly the person is
charged at high opposite polarity. Since static
electric charges cause damages, it is important
when you handle or test electronic components.
CAUTION:
To prevent damages by electrostatic discharge,
follow the guidelines shown below.
• Do not touch ECM connector pins as well as
electronic components soldered to the ECM
circuit board.
• Do not unpack each replacement component
until preparations are completed for the
component.
• Before taking out a component from the
package, connect the package to the normal
grounding line of the vehicle.
• When you intend to slide on the seat, change
the posture from standing to sitting, or walk by
a certain distance to handle a component,
touch an appropriate grounding material.
Wire color
All wiring harnesses are identified using colored jacket.
The wiring harness used for the main circuit in an
electrical system is identified with single color while the
wiring harness used for the sub-circuit is identified with
color stripe. The following rule is used in each wiring
diagram to indicate size and color of a wiring harness.
Legend
1. Red (stripe color)
2. Green (base color)
3. Harness size (0.5 mm
2
)
LNW21ASH000101-X
eg. : 0.5 GRN / RED
1
2
3
