Isuzu N-Series. Service manual - part 684

6E-158    Engine Control System (4HK1) 

5

1.

Turn OFF the ignition.

2.

Disconnect the boost pressure sensor
harness connector.

3.

Turn ON the ignition, with the engine OFF.

4.

Observe the Boost Pressure Sensor
parameter with the Tech 2.

Is the Boost Pressure Sensor parameter less than
the specified value?

0.1 volts

Go to Step 6

Go to Step 7

6

1.

Turn OFF the ignition.

2.

Connect a test lamp between the low
reference circuit of the boost pressure sensor
harness (pin 1 of J-216 connector) and battery
voltage.

3.

Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

—

Go to Step 9

Go to Step 8

7

Important:
The boost pressure sensor may be damaged if the
sensor signal circuit is shorted to a voltage source.

1.

Test the signal circuit between the engine
control module (ECM) (pin 91 of E-111
connector) and the boost pressure sensor (pin
2 of J-216 connector) for the following
conditions:

• A short to battery or ignition voltage
• A short to any 5 volts reference

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 13

Go to Step 12

8

1.

Test the low reference circuit between the
ECM (pin 109 of E-111 connector) and the
boost pressure sensor (pin 1 of J-216
connector) for an open circuit or high
resistance.

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 13

Go to Step 10

9

1.

Turn OFF the ignition.

2.

Inspect for an intermittent and for a poor
connection at the harness connector of the
boost pressure sensor (pin 1 of J-216
connector).

3.

Repair the connection(s) as necessary.

Did you find and correct the condition?

—

Go to Step 13

Go to Step 11

10

1.

Turn OFF the ignition.

2.

Disconnect the ECM harness connector.

3.

Inspect for an intermittent and for a poor
connection on the boost pressure sensor
circuit at the harness connector of the ECM
(pin 109 of E-111 connector).

4.

Repair the connection(s) as necessary.

Did you find and correct the condition?

—

Go to Step 13

Go to Step 12

11

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

Did you complete the replacement?

—

Go to Step 13

—

Step

Action

Value(s)

Yes

No

 Engine Control System (4HK1)    6E-159

12

Important:
Replacement ECM must be programmed.

Replace the ECM. Refer to Engine Control Module
(ECM) Replacement / Fuel Injector ID Code Data
Programming in this section.

Did you complete the replacement?

—

Go to Step 13

—

13

1.

Reconnect all previously disconnected
harness connector(s).

2.

Clear the DTCs with the Tech 2.

3.

Turn OFF the ignition for 30 seconds.

4.

Start the engine.

5.

Operate the vehicle within the Conditions for
Running the DTC.

Did the DTC fail this ignition?

—

Go to Step 2

Go to Step 14

14

Observe the DTC Information with the Tech 2.

Are there any DTCs that you have not diagnosed?

—

Go to Diagnostic 

Trouble Code (DTC) 

List

System OK

Step

Action

Value(s)

Yes

No

6E-160    Engine Control System (4HK1) 

P0335 (Flash Code 15)

Circuit Description
The crankshaft position (CKP) sensor is located on top
of the flywheel housing. There are 56 notches spaced
6

° apart and a 30° section that is open span. This open

span portion allows for the detection of cylinder #1 top
dead center (TDC). The CKP sensor is a magnetic coil
type sensor, which generates an AC signal voltage
based on the crankshaft rotational speed. The engine
control module (ECM) monitors both the CKP sensor
and camshaft position (CMP) sensor signals to ensure
they correlate with each other. If the ECM receives a
certain amount of CMP sensor signal pulses without a
CKP sensor signal, this DTC will set.

Condition for Running the DTC

• DTCs P0336, P0340, P0341 and P1345 are not

set.

• The ignition switch is ON.
• The CMP sensor signal pulse is detected.

Condition for Setting the DTC

• The ECM detects that the CKP sensor pulses are

not generated during engine rotations.

Action Taken When the DTC Sets

• The ECM illuminates the malfunction indicator

lamp (MIL) when the diagnostic runs and fails.

Condition for Clearing the MIL / DTC

• The ECM turns OFF the MIL when the key is

cycled after a current DTC clears.

• A current DTC clears when the diagnostic runs and

does not fail at next driving cycle.

• A history DTC clears after 20 consecutive driving

cycles without a fault. Or clear with the Tech 2 or
accelerator pedal operation.

Diagnostic Aid

• If an intermittent condition is suspected, refer to

Intermittent Conditions in this section.

• Ensure the sensor is tight and the flywheel teeth

are not damaged.

DTC P0335 (Flash Code 15)
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views

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 the Tech 2.

2.

Turn OFF the ignition for 30 seconds.

3.

Start the engine (Note a slight start delay may
be noticed).

4.

Monitor the Diagnostic Trouble Code (DTC)
Information with the Tech 2.

Does the DTC fail this ignition?

—

Go to Step 3

Go to Diagnostic 

Aids

3

1.

Turn OFF the ignition.

2.

Disconnect the crankshaft position (CKP)
sensor harness connector.

3.

Connect a DMM across the CKP sensor
terminals.

4.

Measure the resistance across the CKP
sensor.

Does the CKP sensor resistance measure within
the specified range?

105 – 145 

Ω

Go to Step 4

Go to Step 13

4

1.

Connect a DMM across the CKP sensor
terminals (measure sensor output voltage).

2.

Place the DMM on the AC volt scale.

3.

Start the engine.

4.

Monitor the DMM while accelerating the
engine between idle and W.O.T. (accelerator
pedal full travel).

Does the DMM indicate an AC voltage increase in
accordance with an engine speed increase?

—

Go to Step 5

Go to Step 10

 Engine Control System (4HK1)    6E-161

5

1.

Turn ON the ignition, with the engine OFF.

2.

Connect a DMM between the CKP sensor
harness (pin 1 of E-98 connector) and a
known good ground.

3.

Connect a DMM between the CKP sensor
harness (pin 2 of E-98 connector) and a
known good ground.

Is each DMM voltage within the specified value?

0.4 – 1.4 volts

Go to Step 7

Go to Step 6

6

Is the DMM voltage more than the specified value
at Step 5?

—

Go to Step 9

Go to Step 8

7

1.

Test the CKP sensor circuits between the
engine control module (ECM) (pins 106 and
107 of E-111 connector) and CKP sensor (pins
1 and 2 of E-98 connector) for a short to each
other.

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 15

Go to Step 11

8

1.

Test the CKP sensor circuits between the
ECM (pins 106 and 107 of E-111 connector)
and CKP sensor (pins 1 and 2 of E-98
connector) for the following conditions:

• An open circuit
• A short to ground
• High resistance

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 15

Go to Step 12

9

1.

Test the CKP sensor circuits between the
ECM (pins 106 and 107 of E-111 connector)
and CKP sensor (pins 1 and 2 of E-98
connector) for the following conditions:

• A short to battery or ignition voltage
• A short to any 5 volts reference

2.

Repair the circuit(s) as necessary.

Did you find and correct the condition?

—

Go to Step 15

Go to Step 14

10

1.

Inspect the CKP sensor for tightness. Retest if
the sensor was loose.

2.

Remove the CKP sensor and check for
damage, metal particles on magnet and for
flywheel teeth damage.

Did you find and correct the condition?

—

Go to Step 15

Go to Step 13

11

1.

Turn OFF the ignition.

2.

Inspect for an intermittent and for poor
connections at the harness connector of the
CKP sensor (pins 1 and 2 of E-98 connector).

3.

Repair the connection(s) as necessary.

Did you find and correct the condition?

—

Go to Step 15

Go to Step 14

Step

Action

Value(s)

Yes

No