2007 ISUZU KB P190 engine

ENGINE DRIVEABILITY AND EMISSIONS 6E–43
J1-21 J1-21 Crankshaft Position (CKP) Sensor Signal WHT - - Wave form
or approx. 3.7V Wave form
A or
approx. 7.8V Connect AC V J1-21 J1-6
J1-22 J1-22 No.2 Injector GRN/
WHT Less than
1V Wave form E or 12-14V
Connect DC V J1-22 GND
J1-23 J1-23 No Connection - --- - -- - -
J1-24 J1-24 MAP Sensor Signal GRY Less than 1VApprox.
4.8V Approx.
1.3V Approx.
0.9V Connect DC V J1-24 J1-16
J1-25 J1-25 No Connection - --- - -- - -
J1-26 J1-26 No Connection - --- - -- J1-26 -
J1-27 J1-27 Engine Coolant Temp. (ECT) Sensor Signal GRY Less than
1V
20℃: Approx. 2.4V / 40 ℃: Approx. 1.4V or
4.1V / 60 ℃: Approx. 3.3V / 80 ℃: Approx.
2.5VConnect DC V J1-27 J1-32
J1-28 J1-28 Idle Air Control Valve (IACV) Coil A High BLU Less than
1V Less than 1V / 10-14V
Connect DC V J1-28 GND
J1-29 J1-29 Idle Air Control Valve (IACV) Coil B Low BLU/
BLK Less than
1V Less than 1V / 10-14V
Connect DC V J1-29 GND
J1-30 J1-30 Idle Air Control Valve (IACV) Coil A Low BLU/
WHT Less than
1V Less than 1V / 10-14V
Connect DC V J1-30 GND
J1-31 J1-31 MAP Sensor Power Supply RED Less than
1V Approx.. 5V
Connect DC V J1-31 J1-16
J1-32 J1-32 ECT Sensor, Knock Sensor, Throttle
Position Sensor Ground GRN Continuity
with
ground -
- - Connect ΩJ1-32 GND
Pin
No. B/
Box No. Pin Function
Wire
Color Signal or Continuity
ECM
Connection Tester Position
Key SW Off Key SW
On Engine
Idle Engine
2000rpm Range (+) (-)

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–44 ENGINE DRIVEABILITY AND EMISSIONS
Connector J2 Port: View Looking Into ECM Case
1
17 16
32
PIN32
PIN1
PIN17
PIN16
Pin
No. B/
Box No. Pin Function
Wire
Color Signal or Continuity
ECM
Connection Tester Position
Key SW Off Key SW
On Engine
Idle Engine
2000rpm Range (+) (-)
J2-1 J2-1 Intake Air Temp. (IAT) Sensor Ground GRN Continuity
with
ground -
- - Disconnect ΩJ2-1 GND
J2-2 J2-2 Battery Power Supply RED/ WHT10-14V
Connect DC V J2-2 GND
J2-3 J2-3 Ignition Power Supply BLU/ YELLess than
1V 10-14V
Connect DC V J2-3 GND
J2-4 J2-4 To Data Link Connector No. 6 BLU -
-- - -- - -
J2-5 J2-5 No Connection -- - - - -- - -
J2-6 J2-6 Oxygen Sensor (Ground) PNK Continuity
with
ground -
- - Connect ΩJ2-6 GND
J2-7 J2-7 No Connection -- - - - -- - -
J2-8 J2-8 No Connection -- - - - -- - -
J2-9 J2-9 No Connection -- - - - -- - -
J2-10 J2-10 CO Adjust Signal (W/O Catalystic
Converter) YEL -
-- - -- - -
J2-11 J2-11 Fuel Pump Relay GRN/ WHT10-14V
While relay
is activated; 10-14V
Relay is not
activated;
Less than 1V10-14V Connect DC V J2-11 GND
J2-12 J2-12 No Connection -- - - - -- - -
J2-13 J2-13 A/C Compressor Relay GRY/
RED Less than
1V A/C comp. is operated: Less than 1V
A/C comp. is not operated: 10-14V Connect DC V J2-13 GND
J2-14 J2-14 No Connection -- - - - -- - -
J2-15 J2-15 No Connection -- - - - -- - -
J2-16 J2-16 No Connection -- - - - -- - -
J2-17 J2-17 CO Adjust (W/O Catalystic Converter) RED -
-- - -- - -
J2-18 J2-18 Battery Power Supply RED/ WHT10-14V
Connect DC V J2-18 GND
J2-19 J2-19 No Connection -- - - - -- - -
J2-20 J2-20 Power Steering Pressure Switch GRN/
YEL Less than
1V
Pressure switch is turned on: Less than 1VPressure switch is turned off: 10-14VConnect DC V J2-20 GND
J2-21 J2-21 Oxygen Sensor BLU Less than 1VApprox.
0.4V Wave form D or 0.1 -
0.9V Connect DC V J2-21 J2-6
J2-22 J2-22 Intake Air Temp. (IAT) Sensor (Signal) YEL/
GRN Less than
1V
20℃: Approx. 2.9V / 40 ℃: Approx. 1.8V V
/ 60 ℃: Approx. 1.1V / 80 ℃: Approx. 0.6VConnect DC V J2-22 33

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–45
J2-23 J2-23 Vehicle Speed Sensor (VSS) Signal
(Immobilizer Control
Unit Terminal B8) WHT -
- Wave form C or Approx.
6.5V at 20km/h Connect AC V J2-23 GND
J2-24 J2-24 No Connection -- - - - -- - -
J2-25 J2-25 Tachometer Output Signal BLK/
RED -
- Wave form Wave form
B or
Approx.
4.5V Connect AC V J2-25 GND
J2-26 J2-26 Thermo Relay GRN/
BLK Less than
1V
A/C request is activated: 10-14V
A/C request is not activated: Less than 1VConnect DC V J2-26 GND
J2-27 J2-27 No Connection - - - - - - - - -
J2-28 J2-28 No Connection - - - - - - - - -
J2-29 J2-29 No Connection -- - - - -- - -
J2-30 J2-30 To Data Link Connector No. 2 GRN -
-- - -- - -
J2-31 J2-31 Oxygen Sensor Heater BLU/ WHTContinuity
with
ground - Wave
Form Wave
Form D Connect
ΩJ2-31 GND
J2-32 J2-32 Check Engine Lamp (Immobilizer Control
Unit Terminal B7) BRN/
YEL Less than
1V Less than
1V Lamp is turned on: Less
than 1V
Lamp is turned off: 10-
14V Connect DC V J2-32 GND
Pin
No. B/
Box No. Pin Function
Wire
Color Signal or Continuity
ECM
Connection Tester Position
Key SW Off Key SW
On Engine
Idle Engine
2000rpm Range (+) (-)

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–46 ENGINE DRIVEABILITY AND EMISSIONS
Reference Wave Form
Crankshaft Position (CKP) Sensor Reference W ave Form









0V








Measurem ent Term inal: J1-21(+) J1-6(-)
Measurem ent Scale: 10V/div 5m s/div
Measurem ent Condition: Approxim ately 2000rpm
Vehicle Speed Sensor (VSS) Reference Wave Form








CH1
0V


CH2
0V





M easurem ent Term inal: CH1: ECM J2-23(+) / CH2: VSS 3(+) GND(-)
M easurem ent Scale: CH1: 10V/div / CH2: 10V/div 50m s/div
Measurem ent Condition: Approxim ately 20km /h
Note: The vehicle is w ithout imm obilizer system,
CH1 signal is same as CH2.
Injector Control Signal Reference W ave Form









0V








Measurem ent Term inal: J1-9(+) (No.1 Cylinder) GND(-)
Measurement Scale: 20V/div 5ms/div
Measurem ent Condition: Approximately 2000rpm
Crankshaft Position (CKP) Sensor & Tacho Output Signal
Reference W ave Form
CH1
0V

CH2
0V

Measurement Terminal: CH1: J1-21(+) / CH2: J2-25(+) GND(-)
Measurement Scale: CH1: 2V/div / CH2: 10V/div 5ms/div
Measurement Condition: Approximately 2000rpm
Heated Oxygen Sensor (HO2S) Reference Wave Form









0V








Measurem ent Terminal: J2-21(+) GND(-)
Measurem ent Scale: 500m V/div 500m s/div
Measurement Condition: Approxim ately 2000rpm in Closed Loop
Ignition Coil Control Signal Reference Wave Form








CH1
0V


CH2
0V




Measurement Terminal: CH1: J1-19(+) / CH2: J1-18(+) GND(-)
Measurem ent Scale: CH1: 20V/div / CH2: 20V/div 10m s
Measurement Condition: Approximately 2000rpm

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–47
EVAP Canister Purge Solenoid Reference W ave Form









0V








Measurement Terminal: J1-5(+) GND(-)
Measurement Scale: 20V/div 20ms/div
Frequency: Approximately 16Hz

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–48 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR ECM AND
SENSORS
Engine Control Module (ECM)
The engine control module (ECM) is located on the
intake manifold. The ECM controls the following.
• Fuel metering system
• Ignition timing
• On-board diagnostics for electrical functions.
The ECM constantly observes the information from vari-
ous sensors. The ECM controls the systems that affect
vehicle performance. And it performs the diagnostic
function of the system.
The function can recognize operational problems, and
warn to the driver through the check engine lamp, and
store diagnostic trouble code (DTC). DTCs identify the
problem areas to aid the technician in marking repairs.
The input / output devices in the ECM include analog to
digital converts, signal buffers, counters and drivers.
The ECM controls most components with electronic
switches which complete a ground circuit when turned
on.
Inputs (Operating condition read):
• Battery voltage
• Electrical ignition
• Exhaust oxygen content
• Intake manifold pressure
• Intake air temperature
• Engine coolant temperature
• Crankshaft position • Knock signal
• Throttle position
• Vehicle speed
• Power steering pressure
• Air conditioning request on or off
Outputs (Systems controlled):
• Ignition control
• Fuel control
• Idle air control
• Fuel pump
• EVAP canister purge
• Air conditioning
• Diagnostics functions
Manifold Absolute Pressure (MAP) Sensor
The MAP sensor is a strain gage. A pressure strains the
resistance on the silicon base. At that time the
resistance value changes. And it changes voltage. In
other words it measures a pressure value. It is installed
to the intake manifold. Output voltage of the MAP
sensor is low as pressure is low.
(1) J1 Port
(2) J2 Port
12
C harac t eris t ic of MAP Sens or -R ef erenc e-
0
0.5 1
1.5 2
2.5
3
3.5 4
4.5 5
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 Manifold Abs olute Press ure (KPa) (T ec h2 Reading)
Output Voltage (V)

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–49
Throttle Position Sensor (TPS)
The TPS is a potentiometer connected to throttle shaft
on the throttle body.
The engine control module (ECM) monitors the voltage
on the signal line and calculates throttle position. As the
throttle valve angle is changed when accelerator pedal
moved. The TPS signal also changed at a moved
throttle valve. As the throttle valve opens, the output
increases so that the output voltage should be high.
The throttle body has a throttle plate to control the
amount of the air delivered to the engine.
Engine coolant is directed through a coolant cavity in
the throttle body to warm the throttle valve and to
prevent icing.
Idle Air Control (IAC) Valve
The idle air control valve (IAC) valve is two directional
and gives 2-way control. With power supply to the coils
controlled steps by the engine control module (ECM),
the IAC valve's pintle is moved to adjust idle speed,
raising it for fast idle when cold or there is extra load
from the air conditioning or power steering.
By moving the pintle in (to decrease air flow) or out (to
increase air flow), a controlled amount of the air can
move around the throttle plate. If the engine speed is
too low, the engine control module (ECM) will retract the
IAC pintle, resulting in more air moving past the throttle
plate to increase the engine speed.
If the engine speed is too high, the engine control
module (ECM) will extend the IAC pintle, allowing less
air to move past the throttle plate, decreasing the
engine speed.
The IAC pintle valve moves in small step called counts.
During idle, the proper position of the IAC pintle is
calculated by the engine control module (ECM) based
on battery voltage, coolant temperature, engine load,
and engine speed.
If the engine speed drops below a specified value, and
the throttle plate is closed, the engine control module
(ECM) senses a near-stall condition. The engine control
module (ECM) will then calculate a new IAC pintle valve
position to prevent stalls.
If the IAC valve is disconnected and reconnected with
the engine running, the idle speed will be wrong. In this
case, the IAC must be reset. The IAC resets when the
key is cycled “On” then “Off”. When servicing the IAC, it
should only be disconnected or connected with the
ignition “Off”.
The position of the IAC pintle valve affects engine start-
up and the idle characteristic of the vehicle.
If the IAC pintle is fully open, too much air will be
allowed into the manifold. This results in high idle
speed, along with possible hard starting and lean air/
fuel ratio.
(1) Throttle Position Sensor
(2) Idle Air Control (IAC) Valve
1
2
C harac teris t ic of TPS -R ef erenc e-
0
0.5
1
1.5 2
2.5
3
3.5 4
4.5 5
0 10 2030 405060 7080 90100 Throt t le Angle (% ) (Tec h2 R eading)
Output Voltage (V)
StepCoilAB CDCoil A H igh
(ECM J1-28) On On
Coil A Low
(ECM J1-30) On On
Coil B H igh
(ECM J1-13) On On
Coil B Low
(ECM J1-29) On On

(IAC Valve Close Direction)
(IAC Valve Open Direction)

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–50 ENGINE DRIVEABILITY AND EMISSIONS
Crankshaft Position (CKP) Sensor
The crankshaft position (CKP) sensor, which sends a
signal necessary for deciding on injection timing to the
ECM, is mounted on the left-hand side of the cylinder
block just back of the A/C compressor.
The crankshaft has a 58 teeth press-fit timing disc, from
which the CKP sensor reads the position of the
crankshaft at all the times. It converts this to an
electrical signal, which it sends to the ECM.
Using the 58 X signals per rotation and the timing-mark
signal sent by the CKP sensor, the ECM is able to
accurately calculate engine speed and crank position.
The ECM converts the 58 X signals into square signals.
This converted signal is sent from the ECM terminal J2-
25 to the tachometer.
Knock Sensor (KS)
The knock sensor (KS) contains an element that
converts detection of knock into an electrical signal, and
is mounted on cylinder block wall.
When the ECM receives a signal that indicates knock,
the ECM orders ignition timing to be adjusted to
compensate.
Engine Coolant Temperature (ECT) Sensor
The ECT sensor is a thermistor. A temperature changes
the resistance value. And it changes voltage. In other
words it measures a temperature value. It is installed on
the coolant stream. Low coolant temperature produces
a high resistance.
The ECM supplies 5 volts signal to the ECT sensor
through resisters in the ECM and measures the voltage.
The signal voltage will be high when the engine
temperature is cold, and it will be low when the engine
temperature is hot.

C harac t eris t ic of ECT Sens or -R ef erenc e-
10
100
1000
10000
100000
-20-100 10203040 5060708090100110120 C ool ant T emp. ( deg . C ) ( Tec h2 R eadi ng )
Resistance (ohm) (Solid Line)

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007