2007 ISUZU KB P190 cruise control

Engine Management – V6 – General Information Page 6C1-1–3

1 General Information

The V6 engine management system
incorporates functions and components that
could cause personal injury or vehicle
damage. Refer to 6C1-2 Engine Management –
V6 – Diagnostics, and 6C1-3 Engine
Management – V6 – Service Operations,
before attempting any diagnosis or repairs.
1.1 Introduction
The V6 engine management system is designed to improve engine performance and increase vehicle safety while
meeting the stringent Euro 3 vehicle emission standard. This is achieved by the introduction of the following engine
management sub-systems and components:
• Throttle actuator control (TAC) System – the TAC system allows the engine control module (ECM) to electronically
control the throttle plate opening eliminating the need for the following components:
• mechanical link between the throttle plate and accelerator pedal,
• cruise control module, and
• idle air control motor.
Refer to 3.5 Throttle Actuator Control System for details of the TAC System operation and to 3.6 Cruise Control System for details of the cruise control operation.
This feature results in improved driveability, better fuel economy and emission control.
• W ide band heated oxygen sensor provides a more accurate measurement of the oxygen concentration in the
exhaust gas. Refer to 4.14 Heated Oxygen Sensors.
• Dual spray fuel injectors are now used. The use of this spray pattern is used in engines with two intake valves per
cylinder. The dual spray is achieved by having two openings in the spray orifice disc that are arranged in such a
way that two fuel sprays result, being aimed at each intake valve port. Refer to 4.12 Fuel Injectors.
• Pencil Coil – allows the ignition coil to be fitted directly on the spark plug eliminating the need for spark plug wires.
Refer to 4.15 Ignition Coil and Spark Plug.
The engine management system has a self diagnostic capability, as well as connections to enable diagnosis of faults. If
the ECM recognises operational problems it can alert the driver via the malfunction indicator lamp (MIL) in the instrument
cluster. The ECM also interfaces with other systems in the vehicle as required.
For further information on the air-conditioning system refer to 2A Heater and Air-conditioning,
For the location of fuses, fusible links and relays, refer to 8A Electrical-Body and Chassis.
1.2 Emission Control
ADR 79/01 Emissions Standards
MY2006 I190 Rodeo has been configured to comply with Australian Design Rule 79/01, that adopts the technical
requirements of the European Council Directive 98/69/EC. Commonly referred to as “Euro 3”, the new legislation
modifies the exhaust emissions, compared to the existing ADR 37/01 (or ‘Euro 2’) vehicle emissions standards.
Australian Design Rule 79/01 implements the 'Euro 3' exhaust and evaporative emissions requirements for petrol fuelled
passenger cars, forward control vehicles and passenger off-road vehicles with a gross vehicle mass (GVM) up to 3.5
tonnes. All new vehicles within these categories and first registered from January 1, 2006 must comply with ADR 79/01.
The next table shows a comparison between the existing ADR 37/01 (‘Euro 2’) and ADR 79/01 (‘Euro 3’) Hydrocarbons
Carbon
Monoxide (g/km) Exhaust
(g/km) Evaporative
(g/test) Oxides of Nitrogen
(g/km) Particulate
Matter (g/test)

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Engine Management – V6 – General Information Page 6C1-1–12

Battery Voltage Correction Mode
The ECM monitors the battery voltage circuit to ensure the voltage available to the engine management system stays
within the specified range. A low system voltage changes the voltage across the fuel injectors, which affects the fuel
injector flow rate. In addition, a low system voltage fault condition may cause other engine management system
components to malfunction.
The ECM switches to battery voltage correction mode when the ECM detects a low battery voltage fault condition. W hile
in battery voltage correction mode, the ECM performs the following functions to compensate for the low system voltage:
• Increases the injector on-time to maintain the correct amount of fuel being delivered, and
• Increases the idle speed to increase the generator output.
Limp Mode
The programming in the ECM software allows the engine to run in a back-up fuel strategy or limp mode when the ECM
fails to receive signal inputs from critical sensors or when a critical engine management fault condition exists.
The ECM switches to limp mode to enable the vehicle to be driven until service operations can be performed.
Engine Protection Mode
Engine protection mode is engaged to protect engine components from friction damage in the event of an engine over-
temperature condition being detected by the ECM.
W hen the ECM is in engine protection mode, fuel injectors are systematically disabled and re-activated. The injectors
that have been shut down allow the air being drawn into the engine to assist with engine cooling.
Clear Flood Mode
If the engine is flooded with fuel during starting and will not start, the clear flood mode can be manually selected by
depressing the accelerator pedal to wide open throttle (W OT). In this mode, the ECM will completely disable the fuel
injectors, and will maintain this state during engine cranking as long as the ECM detects a W OT condition with engine
speed less than 1,000 rpm.
3.3 Ignition Control System
The electronic ignition system provides a spark to ignite the compressed air / fuel mixture at the correct time. The ECM
maintains correct spark timing and dwell for all engine operating conditions. The ECM calculates the optimum spark
parameters from information received from the various sensors and triggers the appropriate ignition module / coil to fire
the spark plug.
3.4 Starter Motor Operation
The engine control module controls the activation of the start relay in response to inputs from:
• Ignition switch,
• Battery,
• Immobiliser system, and
• Automatic transmission gear selector position / clutch pedal position switch for vehicles with manual transmissions.
3.5 Throttle Actuator Control System
Description
The throttle actuator control (TAC) system is used to improve emissions, fuel economy and driveability. The TAC system
eliminates the mechanical link between the accelerator pedal and the throttle plate and eliminates the need for a cruise
control module and idle air control motor. The TAC system comprises of:

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Engine Management – V6 – General Information Page 6C1-1–14

Throttle Body Relearn Procedure
The ECM stores values that include the lowest possible TP sensor positions (zero percent), the rest positions (seven
percent), and the spring return rate. These values will only be erased or overwritten if the ECM is reprogrammed or if a
throttle body relearn procedure is performed.
NOTE
If the battery has been disconnected, the ECM
performs a throttle body relearn procedure once
the battery has been reconnected and the ignition
turned on.
The ECM performs a throttle body relearn procedure anytime the ignition is turned on and the following conditions have
been met:
• The engine has been off for greater than 29 seconds,
• The engine speed is less than 40 rpm,
• The vehicle speed is 0 km/h,
• The engine coolant temperature (ECT) is 5 – 60°C; if Tech 2 is used to perform the relearn procedure, the ECT is
5 – 100°C,
• The intake air temperature (IAT) is greater than 5 – 60°C; if Tech 2 is used to perform the relearn procedure, the
IAT is 5 – 100°C,
• The APP sensor angle is less than 15 percent, and
• Ignition voltage is greater than 10 V.
The throttle body relearn procedure is performed 29 seconds after the ignition is turned on. The ECM commands the
throttle plate from the rest position (seven percent open) to full closed (zero percent), then to around 10 percent open.
This procedure takes about six – eight seconds. If any faults occur in the TAC system, a DTC sets. At the start of this
procedure, the Tech 2 TAC Learn Counter parameter should display 0, then count up to 11 after the procedure is
completed. If the counter did not start at 0, or if the counter did not end at 11, a fault has occurred and a DTC should set.
TAC System Default Actions / Reduce Power Modes
The ECM switches to the following reduce power modes if the ECM detects a fault condition in the TAC system:
• If an APP sensor circuit fault or TP sensor circuit fault is detected, the ECM limits engine torque so the vehicle
cannot reach speeds of greater than 100 km/h. The ECM remains in this reduce power mode during the entire
ignition cycle, even if the fault is corrected.
• If there is a fault condition with the throttle actuator control circuits, a throttle actuator command vs. actual position
fault, a return spring check fault, or a TP sensor one circuit fault, the ECM limits engine speed to 2500 rpm and
three – six fuel injectors are randomly disabled. At this time the reduce power indicator is commanded on. The
ECM remains in the reduce power mode during the entire ignition cycle even if the fault is corrected.
NOTE
If a TP sensor one or throttle actuator control
circuit fault is present at the time the vehicle is at
idle, with no accelerator pedal angle, the engine
may stall.
Forced Engine Shutdown
A further safety feature which is built into the TAC system is the ECM will initiate an engine shut down if, the ECM’s
internal monitoring functions detects a serious internal fault, the fuel injectors will be turned off.
3.6 Cruise Control System
The cruise control system integrates with the engine control module (ECM) through the powertrain interface module
(PIM), to control the electronic throttle actuator and maintain the vehicle at the speed set by the driver.

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Engine Management – V6 – General Information Page 6C1-1–15

W hen the cruise control ON-OFF switch, located on the right hand side of the dash panel, is pressed, the PIM, on
receiving the input from the switch, turns on the cruise ON-OFF switch warning lamp to inform the user that the cruise
control has been engaged.
W hen the cruise control switch assembly is pressed to SET/COAST, the PIM on receiving the input, sends a signal via
the serial data bus to the ECM. Providing the pre-conditions for cruise control operation have been met, the ECM
activates cruise control and commands the PIM to turn on the instrument cluster cruise set warning lamp, to inform the
user that cruise control is active. The ECM receives all the various inputs required to maintain the correct speed and then
controls the throttle plate depending on the load on the engine (ascending or descending hills, etc).
The cruise control is deactivated by either pressing the brake pedal, clutch pedal, cruise CANCEL or by the cruise control
ON-OFF button. In each of these instances, the ECM receives an input when any of these switches are activated. For
further information on the cruise control system, refer to 8C Cruise Control – HFV6.
3.7 Brake Torque Management
Brake torque management places limits on engine torque when the brakes are applied, regardless of the accelerator
pedal position (APP). The conditions under which brake torque management occur are as follows:
• The accelerator has been depressed before the brakes are applied,
• The brakes are applied and the ECM receives an input from the stop lamp switch,
• Vehicle speed is greater than 5 km/h,
• Engine speed is greater than 1200 rpm and
• Conditions exist for greater than 2.5 seconds.
W hen brake torque management has been implemented, the torque is reduced by altering the throttle plate opening by
25%. The ECM will monitor the rate at which the vehicle is slowing and adjust the throttle plate opening accordingly.
3.8 Emission Control Systems
Evaporative Emission Control System
The evaporative emission control system used is the
activated carbon (charcoal) canister storage method. Fuel
vapour is drawn from the fuel tank into the canister where it
is held by the activated carbon until the ECM commands the
evaporative emission (EVAP) purge solenoid valve to open.
The ECM energises the EVAP purge solenoid valve by
applying a pulse width modulated (PW M) ground to the
EVAP purge solenoid valve control circuit.
Figure 6C1-1 – 9

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Engine Management – V6 – General Information Page 6C1-1–17

3.9 Serial Data Communication System
The engine control module (ECM) communicates directly with the following control units using the General Motors local
area network (GM LAN) serial data communication protocol:
• Transmission control module (TCM) (if fitted)
• Powertrain interface module (PIM)
The immobiliser control unit (ICU) communicates directly with the PIM using Keyword 2000 serial data communication
protocol. Refer to 11A Immobiliser for further information
As the GM LAN serial data communication protocol is not compatible with the Keyword 2000 serial data communication
protocol, a powertrain interface module (PIM) is integrated to the serial data communication system to perform the
following tasks (Refer to 6E1 Powertrain Interface Module – V6):
• Translate the GM LAN serial data transmitted by the ECM into a Keyword 2000 serial data that can be received
and recognised by the ICU.
• Translate the cruise control switch, automatic transmission power mode switch and 3
rd start switch signal into a GM
LAN serial data that can be received and recognised by the ECM.
3.10 Self Diagnostics System
The ECM constantly performs self-diagnostic tests on the engine management system. W hen the ECM detects a
malfunction, it also stores a diagnostic trouble code (DTC). A stored DTC will identify the problem area(s) and is
designed to assist the technician in rectifying the fault. In addition, DTCs are classified as either Current or History DTC.
Depending on the type of DTC set, the ECM may turn on the
malfunction indicator lamp (MIL) (1) to warn the driver there
is a fault in the Engine Management System.
Figure 6C1-1 – 12
3.11 Service Programming System
The ECM has an Electronically erasable programmable read only memory (EEPROM) where the software and
calibration information required to operate the engine management system are stored.
The ECM features a service programming system (SPS) to flash program the EEPROM in the ECM with the latest ECM
software to provide optimum performance, driveability and emissions control or to program a new ECM.
Flash programming refers to the SPS used to transfer (or download) ECM data from a computer terminal to the vehicle’s
ECM. The system is designed so the vehicle verification procedures are required to eliminate EEPROM tampering that
could increase engine emission levels.
There are three main flash programming techniques:
1 Direct programming (pass through). This is where the vehicle’s data link connector (DLC) is connected directly to a computer terminal. On screen directions are then followed for downloading.
2 Remote Programming. Reprogramming information is downloaded from a computer terminal to Tech 2. Tech 2 is then connected to the vehicle’s DLC. On screen directions are then followed for downloading.
3 Off-board Programming. The off-board programming method is used when a re-programmable ECM must be programmed while it is removed from the vehicle. For example, an independent repair facility may find it necessary
to replace a faulty ECM. On flash programming equipped vehicles, the replacement ECM must be programmed
with data for the specific vehicle identification number (VIN) or the vehicle may not operate properly.

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Engine Management – V6 – General Information Page 6C1-1–19

4 Component Description and
Operation
4.1 A/C Refrigerant Pressure Sensor
The engine control module (ECM) applies a positive 5 V reference voltage and ground to the air-conditioner (A/C)
refrigerant pressure sensor. The A/C refrigerant pressure sensor provides signal voltage to the ECM that is proportional
to the A/C refrigerant pressure. The ECM monitors the A/C refrigerant pressure sensor signal voltage to determine the
refrigerant pressure.
• The A/C refrigerant pressure sensor voltage increases as the refrigerant pressure increases.
• W hen the ECM detects the refrigerant pressure exceeds a predetermined value, the ECM activates the cooling
fans to reduce the refrigerant pressure.
• W hen the ECM detects the refrigerant pressure is too high or too low, the ECM disables the A/C clutch to protect
the A/C compressor from damage.
4.2 Brake Pedal Switch Assembly
Stop Lamp and Initial Brake Apply Switch
The stop lamp and initial brake apply switch assembly (1) is
located on the brake pedal support.
The engine control module (ECM) uses the brake pedal
switch inputs to determine when the brake pedal is
depressed.
The ECM uses the two break pedal switch inputs for:-
• Enabling cruise control,
• Brake torque management,
• Cross referencing the stop lamp switch against the
initial brake apply switch for correct operation.
For further information on brake torque management,
refer to 3.7 Brake Torque
Management.
For further information on the cruise control system, refer to
3.6 Cruise Control System.
Figure 6C1-1 – 13
Stop Lamp Switch
The stop lamp switch contacts are normally open with the brake pedal at rest and closed when the brake pedal is
depressed.
Initial Brake Apply Switch
The initial brake apply switch contacts are normally closed with the brake pedal at rest and open when the brake pedal is
depressed.


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Engine Management – V6 – General Information Page 6C1-1–22

4.6 Clutch Pedal Switch Assembly – Manual
Vehicles Only
The cruise control cancel switch (1) is normally closed when
the clutch pedal is at rest, opening when the pedal is
pressed. Activation of this switch removes the signal to the
ECM which will then deactivate the cruise control. For
further information on the cruise control system, refer to
7A1 Clutch – V6.
Figure 6C1-1 – 19
4.7 Engine Control Module
Located at the right front of the engine assembly, the engine
control module (ECM) monitors input signals from the
various sensors and switches connected to the engine
management system. The ECM processes this information,
to control the following:
• fuel delivery and injection system,
• throttle actuation system,
• ignition system,
• on-board diagnostics,
• the engine cooling fan, and
• the air-conditioner compressor clutch (where fitted).
The ECM supplies 5 V to the various sensors through pull-
up resistors to the internal regulated power supplies.
The ECM controls output circuits such as the injectors, etc.
by applying control signal to the ground circuits of the
components through transistors or a device inside the ECM
called a driver. The exception to this is the fuel pump relay
control circuit. The fuel pump relay is the only ECM
controlled circuit where the ECM controls the 12 V sent to
the coil of the relay. The ground side of the fuel pump relay
coil is connected to engine ground.
The ECM communicates directly with the various control
units within the vehicle using the General Motors local area
network (GM LAN) serial data communication protocol.
Refer to 3.9 Serial Data Communication System.
Figure 6C1-1 – 20

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Engine Management – V6 – Diagnostics Page 6C1-2–15

C-56–28 Not Used
C-56–29 V HI_SIG_3 B1S2 O2 Sensor High Signal (Bank 1 Sensor 2)
C-56–30 Not Used
C-56–31 R/W CRANK_REQ Crank Voltage
C-56–32 B PRKNEU Park/Neutral Switch Signal
C-56–33 Not Used
C-56–34 Not Used
C-56–35 Y START_RLY Starter Relay Coil Control
C-56–36 BR/R BATT + Battery Positive Voltage
C-56–37 Not Used
C-56–38 PU SDI Data Link Connector (DLC) Serial Data
C-56–39 R 5VDC1 5 Volt Reference 1
C-56–40 BR 5VGD5 Low Reference – Ground 5
C-56–41 P RTN_4 B2S2 O2 Sensor Low Signal (Bank 2 Sensor 2)
C-56–42 Y/R FUEL_LVL1 Fuel Level Sensor Signal
C-56–43 Y MAF MAF Sensor Signal
C-56–44 Y PED_POS_2 APP Sensor 2 Signal
C-56–45 Not Used
C-56–46 GR/R CRU_ETC_TCC Brake Switch (S220 – ‘C’) Cruise Cancel Signal
C-56–47 Not Used
C-56–48 Not Used
C-56–49 GR/R AC_CLU A/C Compressor Clutch Relay Control
C-56–50 BR/Y MIL Malfunction indicator Lamp
C-56–51 Not Used
C-56–52 Not Used
C-56–53 BR CRCTL_CLU_SW Clutch Switch (S42) Cruise Cancel Signal
C-56–54 Not Used
C-56–55 R/G CAN_LO_2 GMLAN Serial Data Bus – Low
C-56–56 BR/Y 5VDC3 5 Volt Reference 3
C-56–57 BR/R RTN_3 B1S2 O2 Sensor Low Signal (Bank 1 Sensor 2)
C-56–58 R/Y ACC Accessory Voltage
C-56–59 Not Used
C-56–60 L PED_POS_1 APP Sensor 1 Signal
C-56–61 V HI_SIG_4 B2S2 O2 Sensor High Signal (Bank 2 Sensor 2)
C-56–62 Not Used
C-56–63 Not Used
C-56–64 Not Used

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