Isuzu N-Series. Service manual — part 750

Engine Control System (4JH1) 6E-51

P0500

(B)

24

OFF

Vehicle Speed
Sensor (VSS)
Circuit

• The ignition switch

is ON.

• The engine speed

is higher than 3600
RPM.

• The fuel injection

quantity is more
than 41 mg/strk.

• The ECM detects

that the vehicle
speed is lower than
1.5 km/h (1 MPH)
for 60 seconds.

• Meter (10A) fuse (F-16)

open.

• Sensor ignition voltage

circuit is open circuit or
high resistance.

• Sensor signal circuit is

open circuit, high
resistance, short to
ground, short to battery
or ignition voltage.

• Sensor low reference

circuit is open circuit or
high resistance.

• Poor harness connector

connection.

• Faulty instrument panel

cluster (meter
assembly).

• Faulty VSS.
• Faulty ECM.

P0560

(1)

35

OFF

System Voltage

—

• The ECM detects

that the battery
voltage feed circuit
voltage is more
than 20 volts.

• Incorrect “Jump

Starting”.

• Faulty charging system.
• Faulty ECM.

P0560

(2)

35

OFF

System Voltage

—

• The ECM detects

that the battery
voltage feed circuit
voltage is less than
7 volts.

• Faulty charging system.
• Battery voltage feed

circuit is high resistance.

• Faulty ECM.

P0560

(A)

35

OFF

System Voltage

—

• The PCU battery

voltage feed circuit
voltage is less than
4.5 volts or more
than 27 volts.

• Incorrect “Jump

Starting”.

• Faulty charging system.
• Battery voltage feed or

ground circuit is high
resistance.

• Faulty PCU.

P0561

(A)

18

OFF

Ignition Switch
Circuit

—

• The ECM detects

that the ignition
voltage circuit is
changed ON to
OFF during
initialization.

• ECM main relay control

circuit is short to ground.

• Ignition voltage feed

circuit is intermittently
open circuit or high
resistance.

• Faulty ignition switch.

P0561

(B)

18

OFF

Ignition Switch
Circuit

—

• The ECM detects

internal ignition
voltage feed circuit
is failed after
initialization.

• Faulty ECM.

P0602

(25)

–

ON

Control Module
Not
Programmed

—

• VIN in the ECM is

not programmed.

• VIN is not programmed.

DTC

(Symptom

Code)

Flash
Code

MIL

Status

DTC Name on

Tech 2

Condition for Running

the DTC

Condition for Setting

the DTC

Possible Cause

6E-52 Engine Control System (4JH1)

P0606

(A)

28

ON

Control Module
Internal
Performance

—

• The ECM detects

that the internal
CPU does not
react.

• Faulty ECM.

P0606

(B)

28

ON

Control Module
Internal
Performance

• The accelerator

pedal position is
less than 1%.

• The desired fuel

injection quantity is
0 mg/strk.

• The ECM detects

that the engine
speed is higher
than 2000 RPM.

• Faulty ECM.

P0645

(4)

46

ON

Air Conditioning
(A/C) Clutch
Relay Control
Circuit Low
Voltage

• The ignition switch

is ON.

• The A/C

compressor relay
is once
commanded ON.

• The ECM detects

that the low voltage
condition on the A/
C compressor
relay control circuit
for longer than 3
seconds when the
relay is
commanded OFF.

• A/C compressor relay

ignition voltage feed
circuit on coil side is
open circuit or high
resistance.

• A/C compressor relay

control circuit is open
circuit, high resistance or
short to ground.

• A/C compressor relay is

poor installation.

• Faulty A/C compressor

relay.

• Faulty ECM.

P0645

(8)

46

ON

Air Conditioning
(A/C) Clutch
Relay Control
Circuit High
Voltage

• The ignition switch

is ON.

• The A/C

compressor relay
is once
commanded ON.

• The ECM detects

that the high
voltage condition
on the A/C
compressor relay
control circuit for
longer than 3
seconds when the
relay is
commanded ON.

• A/C compressor relay

control circuit is short to
battery or ignition voltage
circuit.

• Faulty A/C compressor

relay.

• Faulty ECM.

DTC

(Symptom

Code)

Flash
Code

MIL

Status

DTC Name on

Tech 2

Condition for Running

the DTC

Condition for Setting

the DTC

Possible Cause

Engine Control System (4JH1) 6E-53

P0703

(A)

25

ON

Brake Switch
Circuit

• The ignition switch

is ON.

• The engine speed

is higher than 1500
RPM.

• The accelerator

pedal position is
more than 10%.

• The vehicle speed

is higher than 15
km/h (9 MPH).

• The ECM detects

that the brake
pedal 1 switch is
ON (Applied) when
the brake pedal 2
switch is OFF
(Released) for
longer than 30
seconds within the
enabling conditions
ever since ignition
switch is ON.

• Stop (15A) fuse (F-5)

open.

• Brake pedal 1 switch

battery voltage feed
circuit is open circuit or
high resistance.

• Brake pedal 1 switch

signal circuit is open
circuit, high resistance,
short to battery or
ignition voltage.

• Brake pedal 2 switch

ignition voltage feed
circuit is open circuit or
high resistance.

• Brake pedal 2 switch

signal circuit is open
circuit, high resistance,
short to battery or
ignition voltage.

• Misadjusted brake pedal

switch.

• Brake pedal switch is

poor connection.

• Faulty brake pedal

switch.

• Faulty ECM.

P0703

(B)

25

ON

Brake Switch
Circuit

• The ignition switch

is ON.

• The engine speed

is higher than 1500
RPM.

• The accelerator

pedal position is
more than 10%.

• The vehicle speed

is higher than 15
km/h (9MPH).

• The ECM detects

that the brake
pedal 1 switch is
OFF (Released)
when the brake
pedal 2 switch is
ON (Applied) for
longer than 30
seconds.

• Stop (15A) fuse (F-5)

open.

• Brake pedal 1 switch

battery voltage feed
circuit is open circuit or
high resistance.

• Brake pedal 1 switch

signal circuit is open
circuit, high resistance,
short to battery or
ignition voltage.

• Brake pedal 2 switch

ignition voltage feed
circuit is open circuit or
high resistance.

• Brake pedal 2 switch

signal circuit is open
circuit, high resistance,
short to battery or
ignition voltage.

• Misadjusted brake pedal

switch.

• Brake pedal switch is

poor connection.

• Faulty brake pedal

switch.

• Faulty ECM.

DTC

(Symptom

Code)

Flash
Code

MIL

Status

DTC Name on

Tech 2

Condition for Running

the DTC

Condition for Setting

the DTC

Possible Cause

6E-54 Engine Control System (4JH1)

P0704

(6)

57

ON

Clutch Switch
Input Circuit

• The ignition switch

is ON.

• The ECM detects

that the clutch
pedal switch signal
does not change
during the vehicle
speed changes
between 5 km/h
(3MPH) and 80
km/h (50MPH).

• Clutch pedal switch

ignition voltage feed
circuit is open circuit or
high resistance.

• Clutch pedal switch

signal circuit is open
circuit, high resistance,
short to battery or
ignition voltage.

• Misadjusted clutch pedal

switch.

• Clutch pedal switch is

poor connection.

• Faulty clutch pedal

switch.

• Faulty ECM.

P1105

(2)

86

ON

Barometric
Pressure
(BARO) Sensor
Circuit High
Voltage

• The ignition switch

is ON.

• The ECM detects

that the BARO
sensor signal
voltage is more
than 4.4 volts for 1
second.

• Faulty ECM.

P1105

(2)

86

ON

Barometric
Pressure
(BARO) Sensor
Circuit Low
Voltage

• The ignition switch

is ON.

• The ECM detects

that the BARO
sensor signal
voltage is less than
1.5 volts for 1
second.

• Faulty ECM.

P1110

(4)

72

ON

Intake Throttle
Solenoid Circuit
Low Voltage

• The ignition switch

is ON.

• The ECM detects

that the low voltage
condition on the
intake throttle
solenoid valve
control circuit for
longer than 3
seconds when the
solenoid valve is
commanded OFF.

• Intake throttle solenoid

valve ignition voltage
feed circuit is open
circuit or high resistance.

• Intake throttle solenoid

valve control circuit is
open circuit, high
resistance or short to
ground.

• Poor harness connector

connection.

• Faulty intake throttle

solenoid valve.

• Faulty ECM.

P1110

(8)

72

ON

Intake Throttle
Solenoid Circuit
High Voltage

• The ignition switch

is ON.

• The ECM detects

that the high
voltage condition
on the intake
throttle solenoid
valve control circuit
for longer than 3
seconds when the
solenoid valve is
commanded ON.

• Intake throttle solenoid

valve control circuit is
short to battery or
ignition voltage circuit.

• Faulty intake throttle

solenoid valve.

• Faulty ECM.

DTC

(Symptom

Code)

Flash
Code

MIL

Status

DTC Name on

Tech 2

Condition for Running

the DTC

Condition for Setting

the DTC

Possible Cause