ISUZU KB P190 2007 Workshop Repair Manual

6E-54 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Cruise Cancel Switch
This parameter displays the input state of the cruise
cancel switch to the ECM. When the Cruise Cancel
switch is applied, the scan tool displays Off.
Cruise Resume Switch
This parameter displays the input state of the cruise
resume/accel. switch to the ECM. When the Cruise
Resume/Accel. switch is applied, the scan tool displays
On.
Cruise Set Switch
This parameter displays the input state of the cruise
set/coast switch to the ECM. When the Cruise Set/
Coast switch is pushed, the scan tool displays On.
MIL Command (Malfunction Indicator Lamp)
This parameter displays the commanded state of the
malfunction indicator lamp (MIL) control circuit. The
MIL should be On when the scan tool indicates
command On. The MIL should be Off when the scan
tool indicates command Off.
SVS Lamp Command (Service Vehicle Soon)
This parameter displays the commanded state of the
service vehicle soon (SVS) lamp control circuit. The
SVS lamp should be On when the scan tool indicates
command On. The SVS lamp should be Off when the
scan tool indicates command Off.
Limp Home Mode
This parameter indicates the state of the limp-home
mode. None indicates limp-home mode is not applied.
1, 2, 3 and 4 indicates fuel injection quantity reduction
is applied. 2 or higher number inhibits pilot injection. If 4
is indicated, engine running will be stopped when the
vehicle speed is less than 5 km/h (3 MPH) for 5
seconds.
Distance While MIL is Activated
This parameter displays the mileage since the
malfunction indicator lamp (MIL) is turned ON.
Engine Runtime With MIL Active
This parameter displays the engine run time elapsed
since the malfunction indicator lamp (MIL) is turned
ON. The scan tool will display the time in minutes.
Total Engine Overspeed Event
This parameter indicates counter of engine overspeed
event. Counter will be zero if any DTC is cleared.
Total Engine Coolant Overtemperature Event
This parameter indicates counter of engine overheat
event. The counter is active if engine coolant is over
11 0 °C (230 °F). Counter will be zero if any DTC is
cleared. Total Fuel Temperature Overtemperature Event
This parameter indicates counter of fuel temperature
excessively high condition. The counter is active if fuel
temperature is over 95 °C (203 °F). Counter will be zero
if any DTC is cleared.
Total Intake Air Temperature Overtemperature
Event
This parameter indicates counter of intake air
temperature excessively high condition. The counter is
active if intake air temperature is over 55 °C (131 °F).
Counter will be zero if any DTC is cleared.
Immobilizer Function Programmed
This parameter displays the state of the immobilizer
function programming in the ECM. The scan tool will
display Yes or No. Yes indicates the immobilizer
security information is correctly programmed in the
ECM. No indicates the ECM is not programmed or
ECM is reset.
Wrong Immobilizer Signal
This parameter displays the input state of the received
response signal to the ECM. When the ECM received
wrong response signal from the immobilizer control unit
(ICU), the scan tool displays Yes.
Immobilizer Signal
This parameter displays the input state of the response
signal to the ECM. When the ECM received any
response signal from the immobilizer control unit (ICU),
the scan tool displays Yes.
Security Wait Time
This parameter displays the security wait time length in
the ECM. Inactive indicates not in security wait time.
Time indicates under security wait time. This wait time
stage will prevent any further attempts to enter the
security code until the wait time has elapsed. The wait
time will increase each time an incorrect security code
is entered. Note that this parameter is not count
downed. It keeps displaying the same time until that
wait time has elapsed. The ignition switch must be kept
at ON position during the wait time period.

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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-55
Scan Tool Output Controls
Scan Tool Output ControlDescriptions
Fuel Supply Pump Learn Resetting The purpose of this test to reset the fuel supply pump adjustment value.
Important: The fuel supply pump relearn procedure must be done when the fuel supply
pump or engine is replaced, or an ECM from another vehicle is installed. Refer to Fuel
Supply Pump Replacement.
Fuel Pressure Control The purpose of this test is for checking whether the fuel rail pressure is changing when
commanded within 30 to 80MPa (4,350 to 11,600psi) when commanded. Faulty fuel supply
pump, fuel rail pressure (FRP) regulator, pressure limiter valve or other fuel lines could be
considered if the differential fuel rail pressure is large.
Pilot Injection Control The purpose of this test is for checking whether the pilot fuel injection is operated when it is
commanded to ON/ OFF. Faulty injector(s) could be considered if engine noise does not
change when commanded OFF.
Injection Timing Control The purpose of this test is for checking whether the main injection timing is changing when
commanded Retard/ Advance within -5 to 5 °CA.
Injector Force Drive The purpose of this test is for checking whether the fuel injector is correctly operating when
commanded ON. Faulty injector(s) could be considered if it does not create a clicking noise
(solenoid operating noise), contains an interrupted noise or has abnormal noise when
commanded ON.
Cylinder Balance Test The purpose of this test is for checking whether the fuel injector is operating when
commanded ON/ OFF. Faulty injector(s) could be considered if engine does not change
speed when commanded OFF.
Intake Throttle Solenoid Control The purpose of this test is for checking whether the intake throttle valve is correctly moved
with command. Restricted valve movement by foreign materials, excessive deposits or a
faulty valve could be considered if the position difference is large.
EGR Solenoid Control The purpose of this test is for checking whether the EGR valve is correctly moved with
command. Restricted valve movement by foreign materials, excessive deposits or a faulty
valve could be considered if the position difference is large.
Swirl Control Solenoid Control The purpose of this test is for checking whether the swirl control solenoid is operating when
commanded ON. Faulty circuit(s) or a faulty solenoid could be considered if not energizing
when commanded ON.
Turbocharger Solenoid Control The purpose of this test is for checking whether the turbocharger nozzle control actuator is
correctly moved with command. Restricted actuator movement by foreign materials,
excessive deposits, misrouted vacuum hoses, a faulty solenoid or a faulty actuator could be
considered if the actuator is not moved correctly.
Glow Relay Control The purpose of this test is for checking whether the glow relay is operating when
commanded ON. Faulty circuit(s) or a faulty glow relay could be considered if not energizing
when commanded ON.
Glow Plug Lamp Control The purpose of this test is for checking whether the glow indicator lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not operating
when commanded ON.
Malfunction Indicator Lamp (MIL) Control The purpose of this test is for checking whether the MIL is operating when commanded ON.
Faulty circuit(s) or an open circuit could be considered when not operating when
commanded ON.
Service Vehicle Soon (SVS) Lamp Control The purpose of this test is for checking whether the SVS lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not operating
when commanded ON.
Cruise Main Lamp Control The purpose of this test is for checking whether the cruise main lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not operating
when commanded ON.
Cruise Set Lamp Control The purpose of this test is for checking whether the cruise set lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not operating
when commanded ON.

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6E-56 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Scan Tool Does Not Power Up
Circuit Description
The data link connector (DLC) is a standardized 16-
cavity connector. Connector design and location is
dictated by an industry wide standard, and is required
to provide the following:
• Scan tool power battery positive voltage at terminal 16.
• Scan tool power ground at terminal 4. • Common signal ground at terminal 5.
The scan tool will power up with the ignition OFF.
Some modules however, will not communicate unless
the ignition is ON.
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing Scan Tool Does Not Power Up
Step Action Value(s)Yes No
1 Important
: Make sure the scan tool works properly
on another vehicle before using this chart.
1. Turn OFF the ignition.
2. Inspect the Meter (+B) (10A) fuse in the cabin fuse block.
Is the Meter (+B) (10A) fuse open? —
Go to Step 2 Go to Step 3
2 Replace the Meter (+B) (10A) fuse. If the fuse
continues to open, repair the short to ground on
one of the circuits that is fed by the Meter (+B)
(10A) fuse or replace the shorted attached
component.
Did you complete the repair? —
Go to Step 7
—
31. Check each circuit at the data link connector
(DLC) (B-58) for a backed out, spread or
missing terminal.
2. Repair the terminal as necessary.
Did you find and complete the repair? —
Go to Step 7 Go to Step 4
4 Connect a test lamp between the +B circuit (pin 16
of B-58) at the DLC and a known good ground.
Does the test lamp illuminate? —
Go to Step 6 Go to Step 5
5 Repair the open in the battery voltage circuit to the
DLC.
Did you complete the repair? —
Go to Step 7
—
61. Test each ground circuit at the DLC (pins 4
and 5 of B-58) for an open circuit or high
resistance.
2. Repair the circuit(s), clean or tighten ground as necessary.
Did you find and correct the condition? —
Go to Step 7 Go to Intermittent
Conditions
7 1. Connect the scan tool to the DLC.
2. Attempt to turn ON the scan tool.
Does the scan tool ON? —
System OK Go to Step 1

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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-57
Scan Tool Does Not Communicate with CAN Device
Circuit Description
The ECM, transmission control module (TCM) (AISIN
A/T only) and immobilizer control unit (ICU) all
communicate with the scan tool over the controller area
network (CAN) link. The ECM, TCM, ICU and the data
recording module (DRM) communicate with each other
over the same CAN link. If no immobilizer system is
installed, the instrument panel (IP) cluster has a CAN
terminating resistor instead of the ICU.
Diagnostic Aids
The following conditions will cause a loss of CAN serial
data communication between the TCM and ICU or
between the scan tool and any control module: • A CAN serial data circuit open
• A CAN serial data circuit shorted to ground
• A CAN serial data circuit shorted to voltage
• An internal condition within a module or connector on the CAN serial data circuit, that causes a short
to voltage or ground to the CAN serial data circuit
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing Scan Tool Does Not Communicate with CAN Device
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Engine Controls? —
Go to Step 2 Go to Diagnostic
System Check - Engine Controls
2 Important
: Make sure the CANdi module is not
malfunctioning. When functioning properly, the
CANdi module LED will be flashing. In the event of
a problem, the LED will be continually illuminated
or not illuminated.
1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Attempt to establish communication with the listed control modules.
•ECM
• Immobilizer Control Unit (ICU) (If so equipped)
• Transmission control module (TCM) (AISIN A/T only)
Does the scan tool communicate with any of the
listed control modules? —
Go to Step 3 Go to Step 7
3 Does the scan tool communicate with the ECM?
—
Go to Step 4 Go to Lost
Communication with
The Engine Control Module (ECM)
4 Notice:
If no AISIN automatic transmission is
installed, skip to Step 5.
Does the scan tool communicate with the TCM? —
Go to Step 5 Go to Diagnostic
System Check -
Transmission Controls
5 Notice:
If no immobilizer system is installed, skip to
Step 6.
Does the scan tool communicate with the ICU? —
Go to Step 6 Go to Diagnostic
System Check -
Immobilizer Controls
6 Test the CAN Low and High serial data circuit for an
intermittently short to ground or intermittently short
to voltage. Then, test the CAN Low and High serial
data circuit for an intermittently open (based on
which control module did not communicate) at the
connection in the circuit.
Did you find and correct the condition? —
Go to Step 19 System OK

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6E-58 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
71. Inspect for an intermittent, for poor
connections and for corrosion at the data link
connector (DLC) (pins 6 and 14 of B-58).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 19 Go to Step 8
8 Notice:
If no data recording module (DRM) is
installed, skip to Step 9.
1. Turn OFF the ignition.
2. Disconnect the DRM C-139 harness connector.
3. Turn ON the ignition, with the engine OFF.
4. Attempt to communicate with the ECM, TCM and ICU.
Does the scan tool communicate with the ECM,
TCM and ICU? —
Go to Step 14 Go to Step 9
9 1. Turn OFF the ignition.
2. Reconnect the DRM harness connector if disconnected.
3. Disconnect the ECM J1 (E-90) and J2 (C-58) harness connectors.
4. Turn ON the ignition, with the engine OFF.
5. Attempt to communicate with the TCM and ICU.
Does the scan tool communicate with the TCM and
ICU? —
Go to Step 15 Go to Step 10
10 Notice:
If no AISIN automatic transmission is
installed, skip to Step 11.
1. Turn OFF the ignition.
2. Reconnect the ECM J1 (E-90) and J2 (C-58) harness connectors.
3. Disconnect the TCM C-94 and C-95 harness connectors.
4. Turn ON the ignition, with the engine OFF.
5. Attempt to communicate with the ECM and ICU.
Does the scan tool communicate with the ECM and
ICU? —
Go to Step 16 Go to Step 11
11 Notice:
If no immobilizer system is installed, skip to
St ep 1 2.
1. Turn OFF the ignition.
2. Reconnect the ECM J1 (E-90) and J2 (C-58) harness connectors if disconnected.
3. Reconnect the TCM C-94 and C-95 harness connectors if disconnected.
4. Disconnect the ICU B-68 harness connector.
5. Turn ON the ignition, with the engine OFF.
6. Attempt to communicate with the ECM and TCM.
Does the scan tool communicate with the ECM and
TCM? —
Go to Step 17 Go to Step 13
Step
Action Value(s)Yes No

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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-59
121. Turn OFF the ignition.
2. Reconnect the ECM J1 (E-90) and J2 (C-58) harness connectors if disconnected.
3. Reconnect the TCM C-94 and C-95 harness connectors if disconnected.
4. Disconnect the instrument panel (IP) cluster B-23 and B-24 harness connector.
5. Turn ON the ignition, with the engine OFF.
6. Attempt to communicate with the ECM and TCM.
Does the scan tool communicate with the ECM and
TCM? —
Go to Step 18 Go to Step 13
13 Repair the open circuit, short to ground or short to
voltage on the CAN Low or High serial data circuit
between the DLC and ECM, TCM, ICU, DRM or IP
cluster.
Did you complete the repair? —
Go to Step 19
—
14Replace the DRM. Refer to DRM Replacement.
Did you complete the replacement? —
Go to Step 19—
15Important
: Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement? —
Go to Step 19
—
16Important
: Replacement TCM must be
programmed.
Replace the TCM. Refer to TCM Replacement.
Did you complete the replacement? —
Go to Step 19
—
17Important
: Replacement ICU must be
programmed.
Replace the ICU. Refer to ICU Replacement.
Did you complete the replacement? —
Go to Step 19
—
18Replace the IP cluster. Refer to IP Cluster
Replacement.
Did you complete the replacement? —
Go to Step 19
—
19Attempt to establish communication with the ECM,
TCM and ICU.
Does the scan tool communicate with the ECM,
TCM and ICU? —
System OK Go to Step 2
Step
Action Value(s)Yes No

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6E-60 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Lost Communication with The Engine Control Module (ECM)
Circuit Description
The ECM, transmission control module (TCM) (AISIN
A/T only) and immobilizer control unit (ICU) all
communicate with the scan tool over the controller area
network (CAN) link. The ECM, TCM, ICU and the data
recording module (DRM) communicate with each other
over the same CAN link. If no immobilizer system is
installed, the instrument panel (IP) cluster has a CAN
terminating resistor instead of the ICU. Schematic Reference:
Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing Lost Communication with The Engine Control Module (ECM)
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Engine Controls? —
Go to Step 2 Go to Diagnostic
System Check -
Engine Controls
2 Attempt to establish communication with the ECM.
Does the scan tool communicate with the ECM? —Go to Intermittent
Conditions Go to Step 3
3 Check the ECM C-58 and E-90 connectors for poor
connections.
Did you find and correct the condition? —
Go to Step 16 Go to Step 4
4 1. Check the ECM (40A) slow blow fuse, ECM
(B) (10A) fuse and Engine (10A) fuse.
Replace and retest if open. If any fuse
continues to open, repair the short to ground
on each circuit fed by that fuse.
2. Turn OFF the ignition.
3. Disconnect the ECM C-58 harness connector.
4. Turn ON the ignition, with the engine OFF.
5. Connect a test lamp to ground and check for voltage at the ignition voltage supply circuit at
the ECM (pin 72 of C-58).
Does the test lamp illuminate? —
Go to Step 5 Go to Step 13
5 1. Turn OFF the ignition.
2. Disconnect the scan tool from the data link connector (DLC) if connected.
3. Measure the resistance across the CAN Low and High circuits by probing the DLC (pins 6
and 14 of B-58).
Is the resistance within the specified value (parallel
resistance of the 120 Ω resistor in the ECM and the
120 Ω resistor in the ICU or IP cluster should be
60 Ω)? 50 to 70
Ω
Go to Step 7 Go to Step 6
6 1. Turn OFF the ignition.
2. Disconnect the ECM harness connector.
3. Inspect for an intermittent, for poor connections and corrosion at the harness
connector of the ECM (pins 66 and 67 of C-
58).
4. Test for high resistance on each circuit.
5. Repair the connection(s) or circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 16 Go to Step 15

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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-61
71. Check ECM ground for corrosion and
tightness.
2. Clean or tighten grounds as necessary.
Did you find and correct the condition? —
Go to Step 16 Go to Step 8
8 1. Turn OFF the ignition.
2. Reconnect the ECM harness connector if disconnected.
3. Replace the ECM main relay with the heater relay or replace with a known good relay.
4. Turn ON the ignition, with the engine OFF.
5. Attempt to establish communication with the ECM.
Does the scan tool communicate with the ECM? —
Go to Step 14 Go to Step 9
9 1. Turn OFF the ignition.
2. Remove the ECM main relay.
3. Turn ON the ignition, with the engine OFF.
4. Using a test lamp, check for both voltage supply circuits to the ECM main relay (pins 4
and 5 of X-12).
5. Repair the open circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 16 Go to Step 10
10 1. Reinstall the ECM main relay.
2. Turn the ignition ON and OFF while listening of feeling for the ECM main relay click. Wait 7
seconds between transitions.
Does the ECM main relay click when the ignition
switch is turned ON or OFF? —
Go to Step 12 Go to Step 11
11 Repair the ECM main relay ground circuit between
the ECM main relay (pin 2 of X-12) and engine
room ground terminal (C-36) for the following
conditions: •An open circuit
• High resistance or a poor connection at the
ECM main relay or ground terminal
Did you complete the repair? —
Go to Step 16
—
121. Test the battery voltage circuit between the
ECM (pin 73 of C-58) and the ECM main relay
(pin 1 of X-12) for the following conditions:
• An open circuit
• High resistance or a poor connection at ECM or ECM main relay
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 16 Go to Step 15
13 Repair the open in the ignition voltage circuit to the
ECM.
Did you complete the repair? —
Go to Step 16
—
14Replace the ECM main relay.
Did you complete the replacement? —
Go to Step 16—
Step Action Value(s)Yes No

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6E-62 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
15Important
: Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement? —
Go to Step 16
—
161. Turn OFF the ignition.
2. Reconnect all previously disconnected fuse, relay or harness connector(s).
3. Turn ON the ignition, with the engine OFF.
4. Attempt to establish communication with the ECM.
Does the scan tool communicate with the ECM? —
System OK Go to Step 3
Step
Action Value(s)Yes No

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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-63
Engine Cranks but Does Not Run
Description
The Engine Cranks but Does Not Run diagnostic table
is an organized approach to identifying a condition that
causes an engine to not start. The diagnostic table
directs the service technician to the appropriate system
diagnosis. The diagnostic table assumes the following
conditions are met:
• The battery is completely charged and terminals are cleaned and tight.
• The engine cranking speed is normal.
• There is adequate fuel in the fuel tank.
• There is no fuel leak in the fuel line.
• There is no air in the fuel line.
• Filters (air, fuel) are clean.
• Fuse and slow blow fuse are normal. Diagnostic Aids
• If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
Test Description
The number below refers to the step number on the
Circuit/ System Testing.
5. If the fuel rail pressure (FRP) regulator low side
circuits between the ECM and the FRP regulator are
shorted to ground, FRP Regulator Feedback will be
approximately 400mA lower as compared with normal.
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing Engine Cranks but Does Not Run (1of 2)
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Engine Controls? —
Go to Step 2 Go to Diagnostic
System Check -
Engine Controls
2 1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Crank the engine for the specified amount of time.
4. Monitor the DTC Information with a scan tool.
Does the scan tool display any DTCs that failed this
ignition? 15 seconds
Go to Applicable DTC Go to Step 3
3 1. Turn OFF the ignition.
2. Wait 1 minute for the fuel pressure to bleed down from the fuel rail.
3. Turn ON the ignition, with the engine OFF. DO NOT start the engine.
4. Observe the Fuel Rail Pressure parameter with a scan tool.
Does the scan tool indicate the specified value? 0 MPa (0 psi)
Go to Step 4 Go to Step 6
4 Notice:
If the vehicle has run out of fuel, air may
be trapped in the fuel system.
1. Make sure the fuel tank have adequate fuel and the fuel quality is good (take a sample).
2. Observe the Fuel Rail Pressure parameter on the scan tool while cranking over the engine
for 5 seconds.
Does the scan tool indicate more than the specified
value during crank? 20 MPa (2,900
psi)
Go to Step 9 Go to Step 5
5 Observe the FRP Regulator Feedback parameter
on the scan tool while cranking over the engine for
5 seconds.
Does the scan tool indicate more than the specified
value during crank? 1500 mA
Go to 2 of 2 Step 1 Go to Step 8

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