2007 ISUZU KB P190 relay

Engine Management – V6 – Diagnostics Page 6C1-2–123

Step Action Yes No
4 NOTE
Before replacing the 3-way catalytic converter (TW C),
correct any conditions that may have damaged the
converter.
1 Replace the catalytic converter. Refer to the appropriate procedure in 6F Exhaust System – V6.
Did you complete the replacement? Go to Step 5 —
5 1 Using Tech 2, clear the DTC/s.
2 Switch off the ignition for 30 seconds.
3 Start the engine.
4 Operate the vehicle within the conditions for running the DTC.
Does any of the EVAP purge solenoid valve control circuit DTCs fail
this ignition cycle? Go to Step 2 Go to Step 6
6 Using Tech 2, select the DTC display function.
Does Tech 2 display any DTCs? Go to the
appropriate DTC
Table in this Section System OK
When all diagnosis and repairs are completed, clear all DTCs and verify correct operation
7.24 DTC P0443, P0458 or P0459
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0443 – Evaporative Emission Control System Purge Solenoid Circuit Malfunction
• DTC P0458 – Evaporative Emission Control System Purge Solenoid Circuit Low Voltage
• DTC P0459 – Evaporative Emission Control System Purge Solenoid Circuit High Voltage
Circuit Description
The Engine control relay applies ignition positive battery voltage to the evaporative emission (EVAP) purge solenoid.
Using a device called a driver, the ECM applies a pulse width modulated (PW M) ground to the EVAP solenoid control
circuit to purge the fuel vapour from the EVAP canister into the intake manifold.
The driver has a feedback circuit that is pulled-up to a voltage. The ECM monitors the driver feedback circuit to
determine if the control circuit is open, shorted to ground or shorted to a positive voltage.
An EVAP purge solenoid valve control circuit DTC sets if the ECM detects the voltage on the EVAP solenoid control
circuit outside the predetermined range when the solenoid is commanded off.
Conditions for Running the DTC
DTC P0443 and P0458
Runs continuously once the following conditions are met:
• The engine speed is greater than 80 rpm
• The ignition voltage is 10.0 – 16.0 V.
• The ECM has commanded the EVAP Purge Solenoid Valve on and off at least once during the ignition cycle.
DTC P0459
Runs continuously once the following conditions are met:

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Engine Management – V6 – Diagnostics Page 6C1-2–127

DTC P0461, P0462 or P0463 Diagnostic Table
Step Action Yes No
1 Has the Diagnostic System Check been performed?
Go to Step 2 Refer to
4.4 Diagnostic
System Check in this Section
2 1 Switch off the ignition for 30 seconds.
2 Operate the vehicle within the conditions for running the DTC or road test the vehicle under various driving condition.
3 Using Tech 2, select the DTC display function.
Does DTC P0461, P0462, P0463 fail this ignition cycle? Go to Step 3 Refer to Additional
Information in this DTC
3 1 Switch off the ignition.
2 Disconnect the fuel level sensor wiring connector.
3 Switch on the ignition with the engine not running.
4 Using a digital multimeter, measure the voltage between the fuel level signal circuit and the ECM housing.
Does the multimeter indicate 4.8 – 5.2 V? Go to Step 4 Go to Step 5
4 1 Switch off the ignition.
2 Remove ECM Fuse F29 from the engine compartment fuse and relay panel assembly.
3 Using a digital multimeter, measure the resistance between the fuel level sensor low reference circuit and the ECM housing.
NOTE
Install the ECM Fuse F29 to the engine compartment fuse
and relay panel assembly after completing this test.
Does the multimeter indicate less than 5 Ω? Go to Step 7 Go to Step 6
5 Test the fuel level sensor signal circuit for a high resistance, open
circuit, short to ground or short to voltage fault condition. Refer to 8A
Electrical - Body and Chassis for information on electrical fault
diagnosis.
W as any fault found and rectified? Go to Step 9 Go to Step 8
6 Test the fuel level sensor low reference circuit for a high resistance,
open circuit, short to ground or short to voltage fault condition. Refer
to 8A Electrical - Body and Chassis for information on electrical fault
diagnosis.
W as any fault found and rectified? Go to Step 9 Go to Step 8
7 Replace the fuel level sensor. Refer to 6C Fuel System – V6s
.
W as the repair completed? Go to Step 9 –
8 Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 9 –
9
1 Using Tech 2, clear the DTCs.
2 Switch off the ignition for 30 seconds.
3 Start the engine.
4 Operate the vehicle within the conditions for running the DTC.
Do any fuel level sensor DTCs fail this ignition cycle? Go to Step 2 Go to Step 10

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ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–128

Step Action Yes No
10 Using Tech 2, select the DTC display function.
Does Tech 2 display any DTCs? Go to the
appropriate DTC
Table in this Section System OK
When all diagnosis and repairs are completed, check the system for correct operation.
7.26 DTC P0480, P0691 or P0692
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0480 – Cooling Fan Relay 1 Circuit Malfunction
• DTC P0691 – Cooling Fan Relay 1 Circuit Low Voltage
• DTC P0692 – Cooling Fan Relay 1 Circuit High Voltage
Circuit Description
The engine control relay applies ignition positive battery voltage to the ignition circuit of the engine cooling fan relay 1
and relay 2. Using a device called a driver, the ECM performs the following tasks:
• grounds the engine cooling fan relay 1 control signal circuit to operate the small engine cooling fan, or
• grounds the engine cooling fan relay 2 control signal circuit to operate both the small engine cooling fan and the
large engine cooling fan.
The driver has a feedback circuit that is pulled-up to a voltage. The ECM monitors the driver feedback circuit to
determine if the control circuit is open, shorted to ground or shorted to a positive voltage.
A cooling fan relay control circuit DTC sets if the ECM detects a fault condition in the engine cooling fan relay control
circuit.
Conditions for Running the DTC
Run continuously once the following conditions are met:
• the ignition voltage is 10 – 16 V,
• the engine speed is greater than 40 rpm, and
• the ECM driver transitions from on to off or from off to on.
Conditions for Setting the DTC
DTC P0480
The ECM detects an open circuit fault condition in the control circuit of the engine cooling fan relay 1.
DTC P0691
The ECM detects a short to ground fault condition in the control circuit of the engine cooling fan relay 1.
DTC P0692
The ECM detects a short to voltage fault condition in the control circuit of the engine cooling fan relay 1.
Conditions for Clearing DTC
The cooling fan relay control circuit DTCs are Type B DTCs. Refer to 1.4 Diagnostic Trouble Codes in this Section, for
action taken when Type B DTCs set and conditions for clearing Type B DTCs.
Additional Information
• Refer to 6B1 – Engine Cooling – V6 for details of the engine cooling fan operation.

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Engine Management – V6 – Diagnostics Page 6C1-2–129

• For an intermittent fault condition, refer to 5.2 Intermittent Fault Conditions in this Section.
• Since fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic
procedure for shorted terminals or poor wiring connection before replacing any component. Refer to 8A Electrical-
Body and Chassis for information on electrical fault diagnosis.
• To assist diagnosis, refer to 3 W iring Diagrams and Connector Charts in this Section, for the system wiring
diagram and connector charts.
DTC P0480, P0691 & P0692 Diagnostic Table
Step Action Yes No
1 Has the Diagnostic System Check been performed?
Go to Step 2 Refer to
4.4 Diagnostic
System Check in this Section
2 1 Switch off the ignition for 30 seconds.
2 Start the engine.
3 Allow the engine to reach the normal operating temperature.
4 Increase the engine speed to 2,000 rpm for 10 seconds or operate the vehicle within the conditions for setting the DTC.
5 Using Tech 2, select the DTC display function.
Does DTC P0480, P0691 or P0692 fail this ignition cycle? Go to Step 3 Refer to Additional
Information in this DTC
3 1 Remove the appropriate engine cooling fan relay. Refer to 8A
Electrical-Body and Chassis.
2 Connect a test lamp between the ignition voltage circuit of the engine cooling fan relay and the ECM housing.
3 Switch on the ignition with the engine not running.
Does the test lamp illuminate? Go to Step 4 Go to Step 5
4 1 Switch off the ignition.
2 Connect a test lamp between the control circuit of the appropriate engine cooling fan relay and a 12 V.
3 Switch on the ignition with the engine not running.
4 Using Tech 2, command the appropriate engine cooling fan relay on and then off.
Does the test lamp turn on and off when the engine cooling fan relay
is commanded on and off? Go to Step 7 Go to Step 6
5 Repair the high resistance or open circuit fault condition in the ignition
voltage circuit of the engine cooling fan relay. Refer to 8A Electrical -
Body and Chassis for information on electrical wiring repair
procedures.
W as the repair completed? Go to Step 9 —
6 Test the engine cooling fan relay control circuit for a high resistance,
open circuit, short to ground or short to voltage fault condition. Refer
to 8A Electrical - Body and Chassis for information on electrical fault
diagnosis.
W as any fault found and rectified? Go to Step 9 Go to Step 8
7 Replace the faulty engine cooling fan relay. Refer to 8A Electrical-
Body and Chassis.
W as the repair completed? Go to Step 9 —

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Engine Management – V6 – Diagnostics Page 6C1-2–130

Step Action Yes No
8 Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 9 —
9 1 Using Tech 2, clear the DTCs.
2 Switch off the ignition for 30 seconds.
3 Start the engine.
4 Operate the vehicle within the conditions for running the DTC.
Does any of the cooling fan relay control circuit DTCs fail this ignition
cycle? Go to Step 2 Go to Step 10
10 Using Tech 2, select the DTC display function.
Does Tech 2 display any DTCs? Go to the
appropriate DTC
Table in this Section System OK
When all diagnosis and repairs are completed, check the system for correct operation.
7.27 DTC P0500
DTC Descriptor
This diagnostic procedure supports DTC P0500 – Vehicle Speed Sensor Circuit Malfunction (Manual Transmission).
Circuit Description
Vehicle speed information is provided to the engine control module (ECM) by the vehicle speed sensor (VSS). The
ignition control relay applies ignition positive voltage to the VSS, and the ground circuit of the VSS is directly connected
to ground.
The VSS is a Hall effect switch. In conjunction with an 18 tooth reluctor wheel, the VSS provide a signal voltage to the
ECM. The ECM uses this signal voltage to determine vehicle speed.
If the ECM detects no vehicle speed, while other sensors indicate that the vehicle is moving, then DTC P0500 sets.
Conditions for Running the DTC
Runs once the following conditions are met:
• The engine coolant temperature is greater than 40º C,
• the ECM is in fuel shut-off mode, and
• the engine speed is between 1,520 and 3,520 rpm
Conditions for Setting the DTC
The ECM detects a speed of less than 0 km/h for 8 seconds continuously, or 50 seconds cumulative.
Conditions for Clearing the DTC
The vehicle speed sensor circuit malfunction DTC is a Type C DTC. Refer to 1.4 Diagnostic Trouble Codes in this
Section, for action taken when Type C DTCs set and conditions for clearing Type C DTCs.
Additional Information
• For an intermittent fault condition, refer to 5.2 Intermittent Fault Conditions in this Section.
• Refer to 6C1-1 Engine Management – V6 – General Information for details on:
• VSS operation, and
• fuel shut-off mode.

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Engine Management – V6 – Diagnostics Page 6C1-2–143

• To assist diagnosis, refer to 3 W iring Diagrams and Connector Charts in this Section, for the system wiring
diagram and connector charts.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
4 Test signal circuit of the EOP sensor. This circuit should display a voltage within the specified range.
5 Measures the integrity of the EOP sensor low reference circuit. Removal of the ECM Fuse 29 enables the ECM to power down completely prior to the test procedure.
P0521 to P0523 Diagnostic Table
Step Action Yes No
1 Has the Diagnostic System Check been performed?
Go to Step 2 Refer to
4.4 Diagnostic
System Check in this Section
2 1 Switch off the ignition for 30 seconds.
2 Operate the vehicle within the conditions for running the DTC.
3 Using Tech 2, select the DTC display function.
Does DTC P0521, P0522 or P0523 fail this ignition cycle? Go to Step 3 Refer to Additional
Information in this DTC
3 1 Switch off the ignition.
2 Disconnect the EOP sensor wiring connector.
3 Switch on the ignition with the engine not running.
4 Using a digital multimeter, measure the voltage between the EOP sensor 5 V reference circuit and the ECM housing.
Does the multimeter display 4.8 – 5.2 V? Go to Step 4 Go to Step 6
4 1 Connect a 3 A fused jumper wire between the EOP sensor 5 V
reference circuit and the EOP sensor signal circuit.
2 Switch on the ignition with the engine not running.
3 Using Tech 2, observe the EOP sensor parameter.
Does Tech 2 display 780 – 980 kPa? Go to Step 5 Go to Step 7
5 1 Switch off the ignition.
2 Remove ECM / TCM Fuse 29 from the engine compartment fuse and relay panel assembly.
3 Using a digital multimeter, measure the resistance between the EOP sensor low reference circuit and the ECM housing.
NOTE
Install the ECM Fuse 29 to the engine compartment fuse
and relay panel assembly after completing this test.
Does the multimeter display 5 Ω? Go to Step 9 Go to Step 8
6 Test the EOP sensor 5 V reference circuit for an open, short to
ground or high resistance fault condition. Refer to 8A Electrical - Body
and Chassis for information on electrical fault diagnosis.
W as any fault found and rectified? Go to Step 11 Go to Step 10
7 Test EOP sensor signal circuit for short to ground fault condition.
Refer to 8A Electrical - Body and Chassis for information on electrical
fault diagnosis.
W as any fault found and rectified? Go to Step 11 Go to Step 10

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Engine Management – V6 – Diagnostics Page 6C1-2–146

Step Action Yes No
3 1 Switch off the ignition for 30 seconds.
2 Operate the vehicle within the conditions for running the DTC.
3 Using Tech 2, select the DTC display function.
Does DTC P0532 or P0533 fail this ignition cycle? Go to Step 4 Refer to Additional
Information in this DTC
4 1 Switch off the ignition.
2 Disconnect the A/C pressure sensor connector.
3 Switch on the ignition with the engine not running.
4 Using a digital multimeter, measure the voltage between the A/C pressure sensor 5 V reference circuit and the ECM housing.
Does the multimeter display 4.8 – 5.2 V? Go to Step 5 Go to Step 7
5 1 Connect a 3 A fused jumper wire between the A/C pressure
sensor 5 V reference circuit and signal circuit.
2 Switch on the ignition with the engine not running.
3 Using Tech 2, observe the ECM A/C pressure voltage parameter.
Does Tech 2 display 4.8 – 5.2 V?
Go to Step 6 Go to Step 8
6 1 Switch off the ignition.
2 Remove ECM Fuse 29 from the engine compartment fuse and relay panel assembly.
3 Using a digital multimeter, measure the resistance between the A/C refrigerant pressure low reference circuit and the ECM
housing.
NOTE
Install the ECM Fuse 29 to the engine compartment fuse
and relay panel assembly after completing the test.
Does the multimeter display 5 Ω? Go to Step 10 Go to Step 9
7 Test the A/C pressure sensor 5 V reference circuit for a high
resistance, open circuit, short to ground, or short to voltage fault
condition. Refer to 8A Electrical - Body and Chassis for information on
electrical fault diagnosis.
W as any fault found and rectified? Go to Step 12 Go to Step 11
8 Test the A/C pressure sensor signal circuit for a high resistance, open
circuit, short to ground, or short to voltage fault condition. Refer to 8A
Electrical - Body and Chassis for information on electrical fault
diagnosis.
W as any fault found and rectified? Go to Step 12 Go to Step 11
9 Test the A/C pressure sensor low reference circuit for a high
resistance or open circuit condition. Refer to 8A Electrical - Body and
Chassis for information on electrical fault diagnosis.
W as any fault found and rectified? Go to Step 12 Go to Step 11
10 Replace the A/C pressure sensor. Refer to 6C1-3 Engine
Management – V6 – Service Operations.
W as the repair completed? Go to Step 12 —
11 Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 12 —

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Engine Management – V6 – Diagnostics Page 6C1-2–147

Step Action Yes No
12 1 Using Tech 2, clear the DTCs.
2 Switch off the ignition for 30 seconds.
3 Start the engine.
4 Operate the vehicle within the conditions for running the DTC.
Does any of the A/C refrigerant pressure sensor circuit DTCs fail this
ignition cycle? Go to Step 2 Go to Step 13
13 Using Tech 2, select the DTC display function.
Does Tech 2 display any DTCs? Go to the
appropriate DTC
Table in this Section System OK
When all diagnosis and repairs are completed, check the system for correct operation.
7.33 DTC P0560, P0562 or P0563
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0560 – System Voltage Malfunction
• DTC P0562 – System Voltage Low Voltage
• DTC P0563 – System Voltage High Voltage
Circuit Description
Battery voltage is supplied continuously to the engine control module (ECM) through the continuous battery supply
circuit and the ground through the ground connection of the ECM housing to the engine.
Turning the ignition switch on activates the ignition control relay, which directs ignition positive voltage from the battery
to the ECM switched battery supply circuit which activates the ECM. The ECM then applies control voltage to the control
circuit of the engine control relay to activate the engine control relay. The engine control relay supplies ignition voltage
to the various engine management system components.
The ECM monitors the battery voltage circuits to ensure the voltage available to the engine management system stays
within the specified range. Incorrect system voltage may cause incorrect engine management system operation or
component malfunction.
An ECM system voltage DTC sets if the ECM detects the voltage available to any of the ECM voltage supply circuit is
outside the specified range.
Conditions for Running the DTC
DTCs P0560, P0563 and P0563 runs continuously when the engine is running at speeds greater than 1500 rpm
Conditions for Setting the DTC
DTC P0560
The ECM detects the ignition 1, ignition 2 or switched battery supply voltage is out of the specified range for 30 seconds.
DTC P0562
The ECM detects the ECM system voltage is less than 11 V for 5 seconds.
DTC P0563
The ECM detects the ECM system voltage is greater than 16 V.

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