Isuzu KB P190. Manual - part 458

ENGINE CONTROL SYSTEM (4JK1/4JJ1)   6E-215

Circuit/ System Testing DTC P0662

13

1.

Reconnect all previously disconnected fuse or
harness connector(s).

2.

Clear the DTCs with a scan tool.

3.

Turn OFF the ignition for 30 seconds.

4.

Turn ON the ignition, with the engine OFF.

5.

Operate the vehicle within the Conditions for
Running the DTC. You may also operate the
vehicle within the conditions that you
observed from the Freeze Frame/ Failure
Records.

Did the DTC fail this ignition?

—

Go to Step 3

Go to Step 14

14

Observe the DTC Information with a scan tool.

Are there any DTCs that you have not diagnosed?

—

Go to DTC List

System OK

Step

Action

Value(s)

Yes

No

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.

Start the engine.

4.

Monitor the DTC Information with a scan tool.

Does the DTC fail this ignition?

—

Go to Step 3

Go to Diagnostic 

Aids

3

1.

Turn OFF the ignition.

2.

Disconnect the swirl control solenoid valve
harness connector.

3.

Turn ON the ignition, with the engine OFF.

4.

Monitor the DTC Information with a scan tool.

Is DTC P0661 set, but not P0662?

—

Go to Step 5

Go to Step 4

4

1.

Test the control circuit between the ECM (pin
67 of E-90) and the solenoid valve (pin 1 of E-
67) for a short to battery or ignition voltage.

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 7

Go to Step 6

5

Replace the swirl control solenoid valve.

Did you complete the replacement?

—

Go to Step 7

—

6

Important: Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.

Did you complete the replacement?

—

Go to Step 7

—

6E-216   ENGINE CONTROL SYSTEM (4JK1/4JJ1)

7

1.

Reconnect all previously disconnected
harness connector(s).

2.

Clear the DTCs with a scan tool.

3.

Turn OFF the ignition for 30 seconds.

4.

Start the engine.

5.

Operate the vehicle within the Conditions for
Running the DTC. You may also operate the
vehicle within the conditions that you
observed from the Freeze Frame/ Failure
Records.

Did the DTC fail this ignition?

—

Go to Step 3

Go to Step 8

8

Observe the DTC Information with a scan tool.

Are there any DTCs that you have not diagnosed?

—

Go to DTC List

System OK

Step

Action

Value(s)

Yes

No

ENGINE CONTROL SYSTEM (4JK1/4JJ1)   6E-217

DTC P0698 or P0699 (Flash Code 57)

Circuit Description

The ECM provides 5 volts reference voltage through
the reference circuit 3 to the following sensors:

• Accelerator pedal position (APP) sensor 3

• Boost pressure sensor

• Crankshaft position (CKP) sensor

• Intake throttle position sensor

The 5 volts reference circuits are independent of each
other outside the ECM, but are bussed together inside
the ECM. Therefore, a short circuit condition on one 5
volts reference circuit affects the entire 5 volts
reference circuit 3. The ECM monitors the voltage on
the 5 volts reference circuit 3. If the ECM detects the
voltage is excessively low or high, DTC P0698 or
P0699 will set.

Condition for Running the DTC

• The battery voltage is more than 6 volts.

• The ignition switch is ON.

Condition for Setting the DTC

• The ECM detects that the 5 volts reference circuit

3 voltage is less than 4.7 volts. (DTC P0698)

• The ECM detects that the 5 volts reference circuit

3 voltage is less than 5.3 volts. (DTC P0699)

Action Taken When the DTC Sets

• The ECM illuminates the MIL when the diagnostic

runs and fails. Refer to DTC Type Definitions for
Action Taken When the DTC Sets - Type A.

• The ECM limits fuel injection quantity.

• The ECM inhibits pilot injection.

• The ECM inhibits EGR control.

• The ECM inhibits cruise control.

Condition for Clearing the DTC

• Refer to DTC Type Definitions for Condition for

Clearing the MIL/ DTC - Type A.

Diagnostic Aids

• If an intermittent condition is suspected, refer to

Intermittent Conditions in this section.

Engine Controls Schematics

Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views

Circuit/ System Testing DTC P0698

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.

Start the engine.

4.

Monitor the DTC Information with a scan tool.

Does the DTC fail this ignition?

—

Go to Step 3

Go to Diagnostic 

Aids

3

1.

Turn OFF the ignition.

2.

Disconnect the accelerator pedal position
(APP) sensor harness connector.

3.

Connect a DMM between the 5 volts reference
circuit (pin 1 of C-40) and a known good
ground.

4.

Turn ON the ignition, with engine OFF.

Is the DMM voltage more than the specified value?

4.7 volts

Go to Step 8

Go to Step 4

4

Notice:  If no boost pressure sensor is installed,
skip to Step 5.

1.

Leave the DMM connected to the APP sensor
harness connector.

2.

Turn OFF the ignition.

3.

Disconnect the boost pressure harness
connector.

4.

Turn ON the ignition, with the engine OFF.

Does the DMM voltage change to more than the
specified value?

4.7 volts

Go to Step 9

Go to Step 5

6E-218   ENGINE CONTROL SYSTEM (4JK1/4JJ1)

5

1.

Leave the DMM connected to the APP sensor
harness connector.

2.

Turn OFF the ignition.

3.

Disconnect the intake throttle valve harness
connector.

4.

Turn ON the ignition, with the engine OFF.

Does the DMM voltage change to more than the
specified value?

4.7 volts

Go to Step 10

Go to Step 6

6

1.

Leave the DMM connected to the APP sensor
harness connector.

2.

Turn OFF the ignition.

3.

Disconnect the camshaft position (CKP)
sensor harness connector.

4.

Turn ON the ignition, with the engine OFF.

Does the DMM voltage change to more than the
specified value?

4.7 volts

Go to Step 11

Go to Step 7

7

1.

Test the 5 volts reference circuit between the
ECM and the following components for a short
to ground or short to the low reference circuit:

• ECM (pin 7 of C-58) and APP sensor 3

(pin 1 of C-40)

• ECM (pin 20 of E-90) and boost pressure

sensor (pin 3 of E-107)

• ECM (pin 36 of E-90) and intake throttle

position sensor (pin 6 of E-38)

• ECM (pin 37 of E-90) and CKP sensor

(pin 3 of E-52)

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 13

Go to Step 12

8

Replace the APP sensor. Refer to APP Sensor
Replacement.

Did you complete the replacement?

—

Go to Step 13

—

9

Replace the boost pressure sensor. Refer to Boost
Pressure Sensor Replacement.

Did you complete the replacement?

—

Go to Step 13

—

10

Replace the intake throttle valve. Refer to Intake
Throttle Valve Replacement.

Did you complete the replacement?

—

Go to Step 13

—

11

Replace the CKP sensor. Refer to CKP Sensor
Replacement.

Did you complete the replacement?

—

Go to Step 13

—

12

Important: Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.

Did you complete the replacement?

—

Go to Step 13

—

Step

Action

Value(s)

Yes

No