Neutral switch ISUZU KB P190 2007 Workshop Repair Manual

3B-42 POWER-ASSISTED STEERING SYSTEM
CAUTION: When turning the SRS coil fully
counterclockwise, stop turning if resistance is felt.
Further forced turning may damage the cable in the
SRS coil (with SRS air bag).
826RW 014
Legend
(1) Neutral mark


RTW 73BSH001301
16. Remove steering column cover.
17. Disconnect the wiring harness connectors located under the steering column then remove combination
switch and SRS coil assembly (with SRS air bag).
NOTE: The SRS coil is a part of the combination switch
assembly, which cannot be replaced separately.
Therefore, be sure not to remove the SRS coil from the
combination switch assembly (with SRS air bag).

RTW 73BSH001001

Installation
1. Install the combination switch assembly with SRS coil (with SRS air bag).
2. Turn the SRS coil fully counterclockwise, return about 3 turns and align the neutral mark (with SRS
air bag).


3. Connect the wiring harness connectors located at the base of steering column.
4. Install the air conditioning lower duct.
5. Install the steering column cover.
CAUTION: When installing the steering column
cover, be sure to wire (through each harness) as
illustrated so that the harness starter switch,
combination switch and SRS coil will not catch
wiring (with SRS air bag).
825RS048


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ISUZU KB P190 2007

3B-48 POWER-ASSISTED STEERING SYSTEM
430R300007
17. Remove steering column cover.
18. Disconnect the wiring harness connectors located under the steering column.
19. Remove the combination switch assembly with SRS coil.
NOTE: The SRS coil is a part of the combination switch
assembly, which cannot be replaced separately.
Therefore, be sure not to remove the SRS coil from the
combination switch assembly (with SRS air bag).

RTW 73BSH001001
20. Turn the ignition switch to the ACC position.

21. Insert a pin (1) into the hole and push on it. Pull the
key cylinder free.







RUW 53BSH000101

Installation
1. Install lock cylinder assembly.
2. Install the combination switch assembly with SRS coil (with SRS air bag).
3. Turn the SRS coil fully counterclockwise, return about 3 turns and align the neutral mark (with SRS
air bag).
CAUTION: When turning the SRS coil fully
counterclockwise, stop turning if resistance is felt.
Further forced turning may damage the cable in the
SRS coil (with SRS air bag).
826RW 014
Legend
(1) Neutral mark


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ISUZU KB P190 2007

3B-56 POWER-ASSISTED STEERING SYSTEM
9. Turn the SRS coil fully counterclockwise, return
about 3 turns and align the neutral mark (1). (with
SRS air bag)
CAUTION: When turning the SRS coil fully
counterclockwise, stop turning if resistance is felt.
Further forced turning may damage to the cable in
the SRS coil.
826RW 014
10. W hen installing the steering column cover, be sure to
route each wiring harness as illustrated so that the
harnesses do not catch any moving parts.
825RW 017
Legend
(1) Steering Column Cover
(2) Starter Switch Harness
(3) Combination Switch Harness
(4) Inflator Module Harness

11. Install steering wheel and align the setting marks
made when removing. Refer to the adjustment method in case a mark has
not been applied in this section.
NOTE: Confirm SRS and horn harness connector is
fixed by the steering wheel.

RTW 73BSH000701

CAUTION: Never apply force to the steering wheel in
the direction of the shaft by using a hammer o
r
other impact tools in an attempt to remove the
steering wheel. The steering shaft is designed as an
energy absorbing unit.
12. Tighten the steering wheel fixing nut to the specified torque.
Torque: 35 N ⋅
⋅⋅
⋅
m (3.6 kgf ⋅
⋅⋅
⋅
m/26 lb ⋅
⋅⋅
⋅
ft)
13. Support the module and carefully connect the module connector and horn lead, then install inflato
r
module.
NOTE: Pass the lead wire through the tabs on the
plastic cover (wire protector) of inflator to prevent lead
wire from being pinched.
14. Tighten bolts to specified torque.
Torque: 3 N ⋅
⋅⋅
⋅
m (0.3 kgf ⋅
⋅⋅
⋅
m/26 lb ⋅
⋅⋅
⋅
in)
15. Install driver knee bolster (reinforcement).
16. Install instrument panel lower cover.
17. Install the engine hood opening lever.
18. Connect the yellow 2-way SRS connector and horn lead located under the steering column.
19. Connect the battery "-" terminal cable (with SRS ai
r
bag).


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6E-14 Engine Control System (4JH1)
A/C & Neutral Switch Resister, CKP Sensor, APP Sensor and Idle Switch









RTW 76EXF003201

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6E-16 Engine Control System (4JH1)
A/C Control System, Glow Control System, Inhibitor Switch (A/T) and Neutral Switch (M/T)



RTW 76EXF003401

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6E-24 Engine Control System (4JH1)







RTW 66ESF000401

Connector No. C-57
Connector Color Black
Test Adapter No. J-35616-64A
Pin W ire Color Pin Function
82 W HT/BLU Vacuum Pressure Sensor 5
Volts Reference (High Altitude
Only)
83 W HT/RED MAF Sensor 5 Volts Reference
84 BLK/BLU IAT Sensor Signal
85 RED/BLU Vacuum Pressure Sensor Signal (High Altitude Only)
86  Not Used
BLK/W HT Neutral Switch Input (M/T) 87
RED/BLK P & N Position Switch Input (A/T)
88 GRN/RED MAF Sensor Signal
89 GRY ECT Sensor Signal
90 RED CKP Sensor Signal
91 PNK CKP Sensor Signal Output
92 BLK/RED MAF Sensor & IAT Sensor Low Reference
93 BLK/PNK ECT Sensor & Vacuum Pressure Sensor (High Altitude Only) Low
Reference
94 BLK/BLU Glow Relay Control
95  Not Used
96 BRN/RED Turbocharger Solenoid Valve
Control (High Altitude Only)
97 BLK/ORN EGR Solenoid Valve Control
98 W HT CKP Sensor Low Reference
99 RED CAN Low Signal
100 W HT CAN High Signal
101 BLK CKP Sensor Shield Ground
102  Not Used
Connector No. C-57
Connector Color Black
Test Adapter No. J-35616-64A
Pin W ire Color Pin Function
102  Not Used
103  Not Used
105 ORN Engine Shutoff (ESO) Solenoid
Valve Control Signal Output
106 - 121 Not Used




























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6E-36 Engine Control System (4JH1)
Scan Tool Data List
The scan tool Data List contains all engine related
parameters that are available on the scan tool. Use the
scan tool Data List only after the following is
determined: • The Diagnostic System Check - Engine Controls is
completed.
• No diagnostic trouble codes (DTCs) are present.
• On-board diagnostics are functioning properly.
The scan tool values from a properly running engine
may be used for comparison with the engine you are
diagnosing. The scan tool Data List represents values
that would be seen on a normal running engine.
Important:
A scan tool that displays faulty data should not be used.
The scan tool problem should be reported to the
manufacturer. Use of a faulty scan tool can result in
misdiagnosis and unnecessary parts replacement. Onl
y
the parameters listed below are referenced in this
service manual for use in diagnosis.


Scan Tool Parameter Units DisplayedTypical Data Value at
Engine Idle
Typical Data Value at 2000
RPM
Operating Conditions: Engine Idling or 2000 RPM / Engine Coolant Temperature is between 75-85 °C (167-185 °F) /
Accelerator Pedal is Constant / Park or Neutral / Accessories OFF / Vehicle Located at Sea Level
Ignition Switch On/Off On On
System Voltage V 11.0 – 15.0 11.0 – 15.0
ECM Main Relay On/Off On On
Engine Speed RPM 650 - 750 1950 – 2050
Desired Idle Speed RPM 700 700
Injection Pump Speed RPM 325 - 375 975 – 1025
Accelerator Pedal Position % 0.0 5.0 – 7.0
Idle Switch On/Off On Off
Intake Air Temperature °C/°F 20 – 40°C / 68 – 104°F 20 – 40°C / 68 – 104°F
Engine Coolant Temperature °C/°F 75 - 85 °C / 167 - 185 °F 75 - 85 °C / 167 - 185 °F
Fuel Temperature °C/°F 20 – 60°C / 68 – 140°F 20 – 60°C / 68 – 140°F
Barometric Pressure hPa Nearly 1010 hPa at sea level Nearly 1010 hPa at sea level
Vacuum Pressure Sensor hPa Nearly 2020 hPa at sea level Nearly 2020 hPa at sea level
Turbocharger Solenoid Command % 100% at sea level 100% at sea level
EGR Solenoid Command % Nearly 90% Nearly 90%
Mass Air Flow Sensor mg/strk
More than 430 mg/strk at sea
level (with EGR system)
More than 700 mg/strk at sea
level (without EGR system)
More than 430 mg/strk at sea
level (with EGR system)
More than 700 mg/strk at sea
level (without EGR system)
Desired Mass Air Flow mg/strk
More than 430 mg/strk at sea
level (with EGR system)
1500 mg/strk (without EGR
system)
More than 430 mg/strk at sea
level (with EGR system)
1500 mg/strk (without EGR
system)
Actual Injection Quantity mg/strk 6.0 – 9.0 7.0 – 11.0
Desired Injection Quantity mg/strk 6.0 – 9.0 7.0 – 11.0
Actual Injection Timing °CA 1.0 – 4.0 3.0 – 4.5
Desired Injection Timing °CA 1.0 – 4.0 3.0 – 4.5
Neutral Switch On/Off On On
Brake Pedal 1 Switch Applied/ ReleasedReleased Released
Brake Pedal 2 Switch Applied/ ReleasedReleased Released
Clutch Pedal Switch Applied/ ReleasedReleased Released
Vehicle Speed km/h / MPH 0 0

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6E-38 Engine Control System (4JH1)
Intake Air Temperature
This parameter displays the temperature of the intake
air based on a voltage input from the intake ai
r
temperature (IAT) sensor to the ECM. The scan tool will
display a low temperature when signal voltage is high,
and high temperature when the signal voltage is low.
Note that the IAT sensor is internal to the mass air flo
w
(MAF) sensor and the MAF sensor is heated.
Engine Coolant Temperature
This parameter displays the temperature of the engine
coolant based on a voltage input from the engine
coolant temperature (ECT) sensor to the ECM. The
scan tool will display a low temperature when the signal
voltage is high, and a high temperature when the signal
voltage is low.
Fuel Temperature
This parameter displays the temperature of the fuel as
calculated by the fuel injection pump control unit (PCU)
using the signal from the fuel temperature sensor inside
of the PCU.
Barometric Pressure
This parameter displays the barometric pressure as
calculated by the ECM using the signal from the
barometric pressure (BARO) sensor inside of the ECM.
Vacuum Pressure Sensor (High altitude
specification only)
This parameter displays the amount of the vacuum
pressure to the turbocharger wastegate valve. W hen a
high vacuum pressure at a low vacuum pressure
amount to the turbocharger wastegate valve. The scan
tool will display doubled barometric pressure when the
ignition is ON with the engine OFF.
Turbocharger Solenoid Command (High altitude
specification only)
This parameter displays the turbocharger solenoid
valuve control duty ratio commanded by the ECM
terminal (pin 96) using the signal from various senso
r
inputs. W hen a low duty ratio, vacuum pressure to the
turbocharger wastegate valve is controlled to increase.
W hen a high duty ratio, vacuum pressure to the
turbochager wastegate valve is controlled to reduce.
EGR Solenoid Command
This parameter displays the EGR solenoid valve control
duty ratio commanded by the ECM terminal (pin 97)
using the signal from engine speed, and injection
volume and various sensor inputs. W hen a small dut
y
ratio, the EGR valve is controlled to close. W hen a large
duty ratio, the EGR valve is controlled to open.

Mass Air Flow Sensor
This parameter displays the air flow into the engine as
calculated by the ECM based on the mass air flo
w
(MAF) sensor input. The scan tool will display a high
value at higher engine speeds, and a low value at idle.
This can be compared to the Desired Mass Air Flow to
determine MAF sensor accuracy, EGR problem o
r
intake problem. Note that the MAF on the scan tool will
only update with the engine running.
Desired Mass Air Flow
This parameter displays a mass air flow desired by the
ECM based on current driving condition.
Actual Injection Quantity
This parameter displays the injection quantity calculated
by the PCU based on the fuel injection solenoid valve
On time which compensated from the timing device
position and fuel temperature inputs. This can be
compared to the Desired Injection Quantity to determine
fuel system problem.
Desired Injection Quantity
This parameter displays an injection quantity desired b
y
the ECM based on current driving condition using target
injection maps.
Actual Injection Timing
This parameter displays the injection timing calculated
by the PCU based on the timing device position which
determined from the crankshaft position sensor and
camshaft position sensor inputs. This can be compared
to the Desired Injection Timing to determine timing
device problem or fuel system problem.
Desired Injection Timing
This parameter displays injection timing desired by the
ECM based on current driving condition using target
injection timing maps. This timing is compensated b
y
engine coolant temperature, altitude and intake ai
r
temperature, etc.
Neutral Switch
This parameter displays the state of the neutral switch
as determined by the ECM terminal (pin 87) based on
an input from the neutral switch or inhibitor switch.
Brake Pedal 1 Switch
This parameter displays the state of the brake pedal as
determined by the ECM terminal (pin 30) based on an
input from the brake pedal 1 switch. This switch turns
On the stop lamps when the brake pedal is depressed.
The scan tool will display Applied when the brake pedal
is depressed.




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6E-62 Engine Control System (4JH1)
DTC
(Symptom Code) Flash
Code MIL
Status DTC Name on
scan tool Condition for
Running the DTC Condition for
Setting the DTC Possible Cause
P1173
(3) 22 OFF Limitation of
Injection Quantity •
The ignition switch
is ON. •
The ECM detects
an excessive high
coolant temperature
for longer than 30
seconds.
•
Engine overheat.
• Faulty engine cooling system.
• Faulty ECT sensor.

P1173 (7) 22 OFF Limitation of
Injection Quantity
•
The ignition switch
is ON. •
The ECM detects
an excessive high
FT for longer than
30 seconds.
•
Faulty PCU.


P1173 (A) 22 OFF Limitation of
Injection Quantity
•
The ignition switch
is ON. •
The ECM detects
an excessive low
FT for longer than
30 seconds.
•
Faulty PCU.

P1335 (A) 43 ON Crankshaft
Position (CKP)
Sensor Circuit •
The ignition switch
is ON. •
The PCU detects
CKP sensor signal
from the ECM is
faulty.
•
CKP sensor signal output circuit
is open circuit, high resistance,
short to ground, short to battery
or ignition voltage.
• Poor harness connector
connection.
• Faulty PCU.
• Faulty ECM.

P1345 (A) 41 ON Crankshaft
Position (CKP) –
Camshaft Position
(CMP) Correlation

•
The PCU received
faulty fuel injection
pump CMP sensor
signal for 1 second.
•
Faulty fuel injection pump.
• Faulty PCU.

P1520 (A) 47 ON Park/Neutral
Position Switch
Circuit •
The ignition switch
is ON.
• The engine speed
is higher than 1500
RPM.
• The vehicle speed
is higher than 63
km/h (39 MPH)
(M/T) or 78 km/h
(49 MPH) (A/T).
• The clutch pedal is
released. (M/T)
•
The ECM detects
that the neutral
switch signal is
continuously ON
(neutral or P/N
range) during three
consecutive driving
cycles.
•
Manual Transmission
• Neutral switch signal circuit is
short to battery or ignition
voltage.
• Faulty neutral switch.
• Faulty ECM.
• Automatic Transmission
• P & N position switch signal
circuit is short to battery or
ignition voltage.
• Misadjusted inhibitor switch.
• Faulty inhibitor switch.
• Faulty ECM.

P1520 (B) 47 ON Park/Neutral
Position Switch
Circuit •
The ignition switch
is ON.
• The engine speed
is higher than 665
RPM
• The vehicle speed
is lower than 2 km/h
(1.2 MPH).
• The clutch pedal is
released after once
depressed.
•
The ECM detects
that the neutral
switch signal is
continuously OFF
(other than neutral)
during three
consecutive driving
cycles.
•
ECM (10A) fuse (EB-4) open.
• Neutral switch ignition voltage
feed circuit is open circuit or high
resistance.
• Neutral switch signal circuit is
open circuit or high resistance.
• Poor harness connector
connection.
• Faulty neutral switch.
• Faulty ECM.

P1605 (C) 55 ON Control Module
Internal
Performance  •
The ECM detects
internal seed or key
file in EEPROM
data is destroyed.
•
Faulty ECM.

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6E-210 Engine Control System (4JH1)
DTC P1520 (Symptom Code A) (Flash Code 47)
Circuit Description
(Manual Transmission)
The neutral switch is installed on the transmission gea
r
control box. W hen the gear position is neutral, the
switch is closed and the switch signal is provided to the
engine control module (ECM). If the ECM detects the
neutral switch signal is not changed from neutral during
the predetermined engine speed and vehicle speed
range, this DTC will set.
(Automatic Transmission)
The inhibitor switch is installed to the transmission case.
W hen the selector position is P or N range, the switch is
closed and the switch signal is provided to the Emir the
ECM detects the neutral switch signal is not changed
from P or N during the predetermined engine speed and
vehicle speed range, this DTC will set.
Condition for Running the DTC • The ignition switch is ON.
• The engine speed is higher than 1500 RPM.
• The vehicle speed is higher than 63 km/h (39
MPH) (M/T) or 78 km/h (49 MPH) (A/T).
• The clutch pedal is released. (M/T).

Condition for Setting the DTC
• The ECM detects that the neutral switch signal is
continuously ON (neutral or P/N range) during
three consecutive driving cycles.
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
Condition for Clearing the MIL/DTC
Important: • Following conditions must be met two consecutive
driving cycles. (One driving cycle: Ignition switch
ON > Engine run > Vehicle run > Ignition switch
OFF for 10 seconds)
- The engine speed is higher than 1500 RPM
- The vehicle speed is higher than 63 km/h (39 MPH) (M/T) or 78 km/h (49 MPH) (A/T)
- The clutch pedal is released (M/T)

- Other than neutral or P/N range
- After the above procedure is done, a history
DTC clears after 40 consecutive driving cycles
without a fault. Or clear with the scan tool.
Diagnostic Aids
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.

DTC P1520 (Symptom Code A) (Flash Code 47)
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views

Chart for M/T
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 scan tool. 2. Turn ON the ignition, with the engine OFF.
3. Observe the Neutral Switch parameter with the scan tool while shift to neutral and other
positions.
Does the scan tool indicate ON when the position is
neutral and OFF when other than the neutral? 

Go to Diagnostic Aids Go to Step 3
3 1. Turn OFF the ignition. 2. Disconnect the neutral switch harness connector.
3. Turn ON the ignition, with the engine OFF.
4. Observe the Neutral Switch parameter with the scan tool.
Does the scan tool indicate ON? 

Go to Step 4 Go to Step 5
4 1. Test the neutral switch input signal circuit between the engine control module (ECM) (pin
87 of C-57 connector) and the neutral switch (pin
1 of E-11 connector) 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

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