relay ISUZU KB P190 2007 Workshop Repair Manual

Starting System – V6 Page 6D1-2–7

2 Diagnostics
2.1 Diagnostic General Information
NOTE
There is a minimum battery voltage threshold
value. If the battery voltage is below the set value,
the ECU will inhibit cranking. Refer to 6C1-1
Engine Management – V6 – General Information
for further information.
Basic Diagnostic Tools Required

Use of incorrect electrical circuit diagnostic
tools when performing the cruise control
diagnostic procedures could result in
incorrect diagnostic results or damage to
components.
The following electrical circuit testing tools are required to perform the diagnostic procedures detailed in this Section:
• digital multimeter with 10 meg ohms impedance, and
• connector test adapter kit Tool No. KM609.
For further information on the use of these tools, refer to 8A Electrical Body and Chassis.
2.2 Tech 2 Data List
The Tech 2 displays the status of certain starting system parameters.
To view the data list:
1 Connect Tech 2 to the DLC.
2 On Tech 2 select: Engine / V6 Engine / Data Display / Data List / Electrical / Theft Data .
Tech 2 Parameter Units Displayed Typical Display Values
Crank Request Inactive / Active Inactive
Starter Relay Off / On Off
2.3 Diagnostic Systems Check
Step Action Yes No
1
Is the fault specifically isolated to this system / module?
Go to Step 2 Go to 0D Vehicle
Diagnostics
2 1 Connect Tech 2 to the DLC.
2 Ignition ON, engine OFF.
3 On Tech 2 select:
Engine / V6 Engine / Diagnostic Trouble codes / Read
DTC’s.
Are there any set DTC’s? Go to the
appropriate DTC
table in 6C1-2 Engine
Management – V6 – Diagnostics. Refer to 2.5
Starting
System Inoperative / Malfunctioning

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Starting System – V6 Page 6D1-2–10

2.5 Starting System Inoperative /
Malfunctioning
Circuit Description
The battery cable supplies a constant connection from the battery to starter solenoid connector P – 4.
W hen the ignition switch is turned to the START position, 12 V is applied to the ECM connector C – 56 pin 31.
For vehicles with 4 speed automatic transmission, when the transmission is in park (P) or neutral (N), the park / neutral
and back-up switch grounds ECM connector C – 56 pin 32.
The ECM provides a ground for the start relay, ECM connector C – 56 pin 35 to start relay connector X – 13 pin 5.
W hen activated the start relay provides 12 V to starter solenoid connector P – 3 pin 1.
The solenoid closes its switch contacts to connect the battery voltage at the solenoid switch terminal P – 4 terminal B to
the DC motor. The pull-in winding of the solenoid switch is grounded through the DC motor winding and brushes. The
hold-in winding is grounded through the solenoid casing. The DC motor is grounded through the starter motor casing.
Refer to 2.4 W iring Diagram to aid in diagnosis.
Diagnostic Table Notes
Reference to following information will assist when diagnosing starting circuit faults:
1 If the battery, starter motor and fuel system are deemed as serviceable and a ‘no crank’ and / or ‘no start’ condition exists, refer to the following Sections as required:
a 11A Immobiliser for theft deterrent engine crank inhibitor related faults
b 6C1-2 Engine Management V6 Diagnostics, for starter relay circuit faults
2 For all wiring harness fault diagnoses, refer to 8A Electrical Body and Chassis.
3 For wiring harness repairs, refer to 8A Electrical Body and Chassis.
4 Refer to 8A Electrical Body and Chassis for harness routing.
5 Ensure the battery, cables and connections are in good order. Refer to 8A Electrical Body and Chassis.
Diagnostic Table
Step Action Yes No
1
Did you review 1.3 System Operation?
Go to Step 2 Go to 1.3
System
Operation
2 Did you read 2.3 Diagnostic Systems Check
Go to Step 3 Go to 2.3
Diagnostic Systems Check
3 Turn the ignition switch to the START position and then release it.
Did the engine crank or were there any clicking or chattering sounds
from the solenoid? Go to Diagnostic
Table – Slow
Cranking, Solenoid Clicks or Chatters Go to Step 4
4 Inspect fusible link SBF9, refer to 8A Electrical Body and Chassis.
Is fusible link SBF9 blown? Replace the faulty
fusible link (refer to
Note 3).
If the fusible link
blows again, repair
or replace the circuit from SBF9 to the
starter relay X – 13 pin 1 or ignition
switch B – 62 pin 2 (refer to Note 2) Go to Step 5

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ISUZU KB P190 2007

Starting System – V6 Page 6D1-2–12

Step Action Yes No
10
1 Connect Tech 2 to the DLC.
2 Ignition on, engine off.
3 On Tech 2 select: Engine / V6 Engine / Data Display / Data List /
Electrical/Theft Data.
4 On Tech 2 scroll to Crank Request.
5 W hile monitoring Tech 2, turn the ignition switch to START.
Does Tech 2 display the following:
Inactive with the ignition switch in the ON position, Active with the
ignition switch in the START position? Go to Step 15 Go to Step 11
11 1 Disconnect the ECM connector C – 56.
2 Using a multimeter set to measure voltage, back probe between the harness connector C56 – X2 pin 31 and ground.
3 W ith the aid of an assistant, monitor the voltage on the multimeter and turn the ignition switch to START.
• W ith the ignition switch in the START position, the
multimeter should display battery voltage
• W ith the ignition switch in the ON position, the multimeter
should display 0 V
Does the multimeter display as described? Refer to 6C1 - 3
Engine
Management – V6 – Service Operations
for further diagnosis.
Go to Step 21 Go to Step 12
12 Test the ignition switch, refer to 3B Steering.
Is the ignition switch serviceable?
Go to Step 13 Replace the faulty
ignition switch. Refer to 3B
Steering
Go to Step 21
13 Check for short to ground or open circuit from the ignition switch start
terminal to the ECM connector C – 56 pin 31.
W as the circuit serviceable? Go to Step 14 Repair as required
(refer to Note 2).
Go to Step 21
14 Check for short to ground or open circuit from the ignition switch
terminal B1 to the fuse SBF5.
W as the circuit serviceable? Go to Step 2 Repair as required
(refer to Note 2).
Go to Step 21
15 NOTE
This procedure is only required on vehicles fitted with
manual transmissions. If the vehicle is fitted with an
automatic transmission, go to Step 16
1 Scroll to Starter Relay
2 W hile monitoring Tech 2, turn the ignition switch to START.
Does Tech 2 display the following:
Off with the ignition switch in the ON position,
On with the ignition switch in the START position?
Go to Step 21 Go to Step 16

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Starting System – V6 Page 6D1-2–13

Step Action Yes No
16 1 Scroll to Starter Relay
2 Ensure the transmission is in park (P) or neutral (N).
3 W hile monitoring Tech 2, turn the ignition switch to START.
Does Tech 2 display the following:
Off with the ignition switch in the ON position,
On with the ignition switch in the START position?
Go to Step 18 Go to Step 17
17 1 Disconnect the ECM connector C – 56.
2 Using a multimeter set to measure voltage, back probe between the harness connector C – 56 pin 32 and ground.
3 W ith the aid of an assistant, monitor the voltage on the multimeter.
• Place the transmission in park (P), the multimeter should
display 0 V
• Place the transmission in neutral (N), the multimeter should
display 0 V
Does the multimeter display as described? Refer to 6C1 - 3
Engine
Management – V6 – Service Operations
for further diagnosis.
Go to Step 21 For vehicles fitted
with the 4 speed automatic
transmission refer
to 7C2 Automatic Transmission –
4L60E – On-vehicle Servicing for further
diagnosis of the
park / neutral and back-up switch.

Go to Step 21
18 Test the starter relay.
Refer to 6C1-2 Engine Management – V6 – Diagnostics.
Is the starter relay serviceable? Go to Step 19 Repair or replace
as required
Go to Step 21
19 1 Using a multimeter set to measure voltage, back probe between
the harness connector P – 3 pin 1 and ground.
2 W ith the aid of an assistant, monitor the voltage on the multimeter.
• Turn the ignition switch to START, the multimeter should
display 7.0 V
Does the multimeter display as described? Repair or replace
the starter motor as required.
Refer to 4
Major
Service Operations.
Go to Step 21 Go to Step 20
20 Check for short to ground or open circuit from connector P – 3 pin 1
and the starter relay connector X-13 pin 2.
W as the circuit serviceable? Go to Step 2 Repair as required
(refer to Note 2).
Go to Step 21
21 Operate the system in order to verify the repair.
Did you correct the condition? System OK Go to Step 2
When all diagnosis and repairs are completed, check the system for correct operation.

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Starting System – V6 Page 6D1-2–16

Engine Compartment Relay And Fuse Panel


Figure 6D1-2 – 4

1 Remove fuses SBF5 and SBF9 from the engine compartment fuse panel to disable the ignition and prevent the engine from starting, refer to 8A Electrical Body and Chassis.
2 Chock the wheels.
3 For vehicles fitted with automatic transmission ensure the transmission is in P (park) or N (neutral) and the hand brake is applied.
4 Ensure the engine is at room temperature or normal operating temperature and in good working order.
Bad Connection Test
A bad connection appears as a voltage reading when the multimeter leads are connected to two different positive (or
negative) connections.
1 Using a multimeter set to measure voltage, connect the multimeter’s positive lead to the positive battery post.
2 Connect the multimeter’s negative lead to the starter motor M terminal.
3 Record the voltage that displayed during cranking.
4 Repeat this with the multimeter’s negative lead connected to the solenoid switch connector P – 4 pin B (circuit 1).
5 Also repeat this connecting the multimeter’s negative lead to the battery cable strands.
6 Restore all connections that show a significant resistance (voltage reading).

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Battery Page 6D1-3–11

b W ait 15 seconds for the battery to recover.
8 If possible, set the selector to 50% of rapid discharge current (or three times the 20 hour discharge rate).
9 Apply the load test for 10 seconds and record the battery voltage. If one cell is faulty it will gas excessively or overheat. This indicates a faulty battery.
10 Recharge the battery if the voltage is at or below the minimum voltage specified by the HRD manufacturer (or 9.6 V).
11 Replace the battery if the voltage is below the minimum voltage specified by the HRD manufacturer (or below 9.6 V after the battery is charged and the test is repeated). Refer to 4.1 Battery.
12 Connect the battery positive terminal.
13 Connect the battery negative terminal.
Alternate Load Test
If HRD test equipment is not available, test the battery as follows:
1 Read and obey the safety precautions for working with batteries, refer to 2 Safety Precautions.
2 Ensure the state of the battery is at least 65% charged. Refer to 3.3 Hydrometer Test.
3 Connect a voltmeter (1) between the battery terminals.
4 Turn the headlights on to high-beam for 10 seconds to remove any surface charge from the battery.
5 Remove fuses EB11 and EB12 from the engine compartment fuse and relay housing. This prevents
vehicle ignition and fuel injection while cranking the
engine.
6 Crank the engine and read the voltmeter. At temperatures above 5°C, the voltage of a fully charged
battery should not fall below 9.6 V.
NOTE
• If the battery and engine temperatures are
below 5 °C, the voltage may fall to 9 V.
• Try to avoid activating the starter motor
continuously for more than 30 seconds. If
activating the starter motor for 30 seconds,
allow the starter motor to cool for 3 minutes.
7 Replace the battery if a cell gasses excessively or overheats or if the voltage falls away quickly.
Figure 6D1-3 – 6
3.5 Battery Current Draw Test
The following test determines if excess current is being drawn from the battery whilst the vehicle has all accessories
turned off. Excess current draw will cause the battery to go flat if the vehicle is not started for an extended period.
Test Preparation
1 Read and obey the safety precautions for working with batteries, refer to 2 Safety Precautions.
2 If the battery is flat, temporarily install a good battery for the duration of the test.
3 Ensure the vehicle starts and the accessories operate normally.
4 Ensure the theft deterrent system operates normally. Refer to 11A Immobiliser.
5 Open all the side windows for access purposes.
6 Switch the ignition off.
7 Check that all interior illumination is off, including any compartment lighting.
8 Close all doors.

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Battery Page 6D1-3–12

9 Lock the doors and activate the theft deterrent system to arm the vehicle.
10 If the multimeter contains fuses, check they are serviceable.
Test Procedure
1 Switch the multimeter to the mA current range (1).
2 Connect the positive test lead (2) to the fused mA terminal of the multimeter.
3 Connect the negative test (3) lead to the common terminal of the multimeter.
4 Connect large alligator clips to the ends of both test leads.
Figure 6D1-3 – 7
5 Connect the negative test lead clip to the threads of the battery negative terminal clamp (1).
6 Connect the positive lead’s clip to the threads of a convenient engine bolt (2).

Do not turn on the ignition switch while this
test is in progress. It will blow the
multimeter’s low current fuse.
7 Check the multimeter connections are secure.
8 Disconnect the vehicle’s main electrical earth by removing the battery negative terminal cable retaining
nut (3) and separating the cable from the battery
clamp.
Figure 6D1-3 – 8
9 Read the vehicle’s battery saver current on the multimeter. The multimeter reading should be within 16 – 30 mA (fluctuating).
10 If the multimeter reading is higher than specified, refer to Fault Diagnosis in this Section, otherwise restore the vehicle to its prior condition, refer to Restore in this Section.
Fault Diagnosis

Do not open any doors during this inspection.
If the doors must be opened, reinstall the
battery terminal to the battery clamp to
protect the multimeter's fuse from blowing.
Alternatively, use the higher (10 A) fuse rated
terminal on the multimeter until the source of
the higher current draw has been found.
1 Visually inspect the vehicle for illuminated lamps and components activated by energised relays.
2 If the cause of the excessive current draw is not apparent, remove one fuse (or circuit breaker) at a time to determine the circuit group that is drawing excess current. Refer to 8A Electrical Body & Chassis for fuse grouping
location.

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ISUZU KB P190 2007

Powertrain Interface Module – V6 Page 6E1–29

Intermittent Fault Conditions
8.1 Intermittent Conditions Diagnostic Table
Description
A fault condition is intermittent if one of the following conditions exists:
• The fault condition is not always present.
• The fault condition cannot be presently duplicated.
• There is no Current DTC but a History DTC is stored.
Diagnostic Table
Checks Actions
Preliminary
• Perform the Preliminary Checks, refer to 7.1 Diagnostic Requirements,
Precautions and Preliminary Checks.
• Gather information from the customer regarding the conditions that trigger the
intermittent fault such as:
• At what engine or ambient temperature range does the fault occur?
• Does the fault occur when operating aftermarket electrical equipment inside
the vehicle?
• Does the fault occur on rough roads or in wet road conditions?
• If the intermittent fault is a start and then stall condition, check immobiliser system.
Refer to 11A Immobiliser.
Harness / Connector Install Tech 2 and perform the Tech 2 Intermittent Fault Tests. Refer to 4.1 Diagnostic General Descriptions for information on Tech 2 ECU diagnostic
tests.
W arning Indicator The following conditions may cause an intermittent Malfunction Indicator Lamp fault with
no DTC listed:
• Electromagnetic Interference (EMI) caused by a faulty relay, ECM controlled
solenoid, switch or other external source.
• Incorrect installation of aftermarket electrical equipment such as the following:
• mobile phones,
• theft deterrent alarms,
• lights, or
• radio equipment.
• Loose PIM ground connections.

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Powertrain Interface Module – V6 Page 6E1–30

Checks Actions
Temperature Related The Tech 2 Freeze Frame / Failure Records or Snapshot data may be used if applicable
to the fault condition. Refer to 4.1 Diagnostic General Descriptions for information on
Tech 2 ECU diagnostic tests.
• If the intermittent fault is heat related, review the Tech 2 data in relationship to the
following:
• high ambient temperature,
• underhood / engine generated heat,
• circuit generated heat due to a poor electrical connection or high electrical
load, and
• higher than normal load conditions (towing, etc.).
• If the intermittent fault is related to cold ambient or engine temperature, review the
Tech 2 data in relationship to the following:
• low ambient temperature, and
• the fault condition that occurs only on a cold start situation.
Additional Tests
• Check for incorrect installation of aftermarket electrical equipment such as the
following:
• mobile phones,
• theft deterrent alarms,
• lights, or
• radio equipment.
• Check for electromagnetic Interference (EMI) caused by a faulty relay, ECM
controlled solenoid or switch. The fault is triggered when the relay or solenoid is
activated.
• Check the A/C compressor clutch and some relays that contain a clamping diode
or resistor for an open circuit.
• Check the generator for a faulty rectifier bridge that may allow A/C noise into the
PIM electrical circuit.
When all diagnosis and repairs are completed, check the engine management system for correct operation.

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Powertrain Interface Module – V6 Page 6E1–39

6 This step tests the internal GM LAN CAN_HI circuit in the PIM.
7 This step tests the internal GM LAN CAN_LO circuit in the PIM.
DTC U2106 Diagnostic Table
Step Action Yes No
1
Has the Diagnostic System Check been performed?
Go to Step 2 Refer to
7.2 Diagnostic
System Check
2 1 Switch off the ignition for 10 seconds.
2 Operate the vehicle within the conditions for setting DTC U2106.
3 Using Tech 2, select the DTC display function.
Does DTC U2106 fail this ignition cycle? Go to Step 3 Refer to
Additional
Information in this Section
3 Using Tech 2, attempt to communicate with the TCM.
Does Tech 2 communicate with the TCM? Go to Step 9 Go to Step 4
4 Test the following TCM circuits for a high resistance, open circuit or
short to ground fault condition. Refer to 8A Electrical - Body and
Chassis for information on electrical diagnosis:
• 12 V battery supply voltage circuit,
• 12 V accessory supply circuit,
• Ignition Control Relay 12 V supply circuit, and
• all TCM ground connections.
Has any fault been found and rectified? Go to Step 10 Go to Step 5
5 Test serial data circuits between the TCM and PIM for a high
resistance or open circuit fault condition. Refer to 8A Electrical - Body
and Chassis for information on wiring circuit testing and repair.
Has any fault been found and rectified? Go to Step 10 Go to Step 6
6 1 Disconnect the PIM harness connector.
2 Using a digital multimeter, measure the resistance between the two CAN_LO terminals of the PIM.
NOTE
Refer to 5 GM LAN Serial Communication Circuit and
6 Wiring Diagram and Connector for the appropriate GM
LAN component terminal identification.
Does the digital multimeter display infinity? Go to Step 9 Go to Step 7
7
Using a digital multimeter, measure the resistance between the two
CAN_HI terminals of the PIM.
Does the digital multimeter display infinity? Go to Step 9 Go to Step 8
8
Replace the TCM. Refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Servicing.
Has the repair been completed? Go to Step 10 —
9 Replace the PIM. Refer to 11.2 Powertrain Interface Module.
Has the repair been completed? Go to Step 10 —

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