Suzuki 2007 XL7, Руководство по обслуживанию

Страница: 311 / 3159

Engine Electrical Devices: 1C-5
ECM Function
The ECM can supply 5 volts or 12 volts to the various
sensors or switches. This is done through pull-up
resistors to the regulated power supplies within the
ECM. In some cases, even an ordinary shop voltmeter
will not give an accurate reading because the resistance
is too low. Therefore, a DMM with at least 10 megaohms
input impedance is required in order to ensure accurate
voltage readings.
The ECM controls the output circuits by controlling the
ground or the power feed circuit through the transistors
or a device called an output driver module.
EEPROM
The electronically erasable programmable read only
memory (EEPROM) is a permanent memory that is
physically part of the ECM. The EEPROM contains
program and calibration information that the ECM needs
in order to control the powertrain operation.
Special equipment, as well as the correct program and
calibration for the vehicle, are required in order to
reprogram the ECM.
Theft Deterrent System Frequency Code
Programming
This vehicle is equipped with a theft deterrent system
which interfaces with the ECM. If the ECM is replaced,
program the new ECM with the frequency code of the
theft deterrent module that is currently on the vehicle.
The vehicle will not start until this procedure is
completed.
KS Module
The ECM employs an internal integrated circuit to
continuously monitor the knock control evaluation circuit.
The knock sensor (KS) module contains the circuitry that
allows the ECM to utilize the knock sensor (KS) signals
and diagnose the KS sensors and circuitry. If the ECM
detects a fault in the ability of the KS module to sample
these signals, a DTC sets.
Data Link Connector (DLC)
The data link connector (DLC) is a 16-pin connector that
provides the technician a means of accessing serial data
for aid in the diagnosis. This connector allows the
technician to use a scan tool in order to monitor the
various serial data parameters, and display the DTC
information. The DLC is located inside of the drivers
compartment, underneath the dash.
Malfunction Indicator Lamp (MIL)
The malfunction indicator lamp (MIL) is inside of the
instrument panel cluster (IPC). The MIL is controlled by
the ECM and illuminates when the ECM detects a
condition that affects the vehicle emissions.
ECM Service Precautions
The ECM, by design, can withstand the normal current
draws that are associated with the vehicle operations.
However, care must be used in order to avoid
overloading any of these circuits. When testing for opens
or shorts, do not ground or apply voltage to any of the
ECM circuits unless the diagnostic procedure instructs
you to do so. These circuits should only be tested with a
DMM.
Emissions Diagnosis For State I/M Programs
This OBD II equipped vehicle is designed to diagnose
any conditions that could lead to excessive levels of the
following emissions:
• Hydrocarbons (HC)
• Carbon monoxide (CO)
• Oxides of nitrogen (NOx)
• Evaporative emission (EVAP) system losses
Should this vehicles on-board diagnostic system (ECM)
detect a condition that could result in excessive
emissions, the ECM turns ON the MIL and stores a DTC
that is associated with the condition.
Aftermarket (Add-On) Electrical And Vacuum
Equipment
CAUTION
!
Do not attach add-on vacuum operated
equipment to this vehicle. The use of add-on
vacuum equipment may result in damage to
vehicle components or systems.
CAUTION
!
Connect any add-on electrically operated
equipment to the vehicle's electrical system
at the battery (power and ground) in order to
prevent damage to the vehicle.
Aftermarket, add-on, electrical and vacuum equipment is
defined as any equipment installed on a vehicle after
leaving the factory that connects to the vehicles
electrical or vacuum systems. No allowances have been
made in the vehicle design for this type of equipment.
Add-on electrical equipment, even when installed to
these strict guidelines, may still cause the powertrain
system to malfunction. This may also include equipment
not connected to the vehicle electrical system, such as
portable telephones and radios. Therefore, the first step
in diagnosing any powertrain condition is to eliminate all
of the aftermarket electrical equipment from the vehicle.
After this is done, if the problem still exists, the problem
may be diagnosed in the normal manner.