2007 ISUZU KB P190 coolant

Engine Management – V6 – Diagnostics Page 6C1-2–61

• DTCs P0341, P0342, P0343, ran and passed:
• The engine is running.
• The ECM has learned the camshafts position.
DTC P0016
Run continuously once the following conditions are met.
• DTCs P0335, P0336, P0338, P0341, P0342 and P0343 ran and passed:
• The calculated engine oil temperature is less than 95 °C.
• The engine coolant temperature is 20 – 90 °C.
• The engine is running for greater than 5 seconds.
Conditions for Setting the DTC
DTC P0008
The ECM detects that both camshafts on bank 1 of the engine are misaligned with the crankshaft.
DTC P0009
The ECM detects that both camshafts on bank 2 of the engine are misaligned with the crankshaft.
DTC P0016
The ECM detects the following deviation in the correlation between the camshaft position and the crankshaft position for
greater than 10 minutes:
• a camshaft position is too advanced in relationship to the crankshaft, or
• a camshaft position is too retarded in relationship to the crankshaft.
Conditions for Clearing DTC
The CKP / CMP sensor correlation DTCs are Type B DTCs. Refer to 1.4 Diagnostic Trouble Codes in this Section, for
action taken when Type B DTCs set and conditions for clearing Type B DTCs.
Additional Information
• Refer to 6C1-1 Engine Management – V6 – General Information for details of the CMP system operation.
• Inspect the engine for recent engine mechanical repairs. Incorrect camshaft, camshaft actuator or timing chain
installation will trigger these DTCs.
• The engine oil condition has a major impact on the operation of the camshaft actuator.
• A low oil level may set these DTCs.
• For an intermittent fault condition, refer to 5.2 Intermittent Fault Conditions in this Section.
• Since fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic
procedure for shorted terminals or poor wiring connection before replacing any component. Refer to 8A Electrical -
Body and Chassis for information on electrical fault diagnosis.
• To assist diagnosis, refer to 3 W iring Diagrams and Connector Charts in this Section, for the system wiring
diagram and connector charts.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
3 A fault condition in any of the listed sensors will trigger these DTCs.
5 Incorrect camshaft, camshaft actuator or timing chain installation will trigger these DTCs.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–75

Step Action Yes No
9 1 Using Tech 2, clear the DTCs.
2 Switch off the ignition for 30 seconds.
3 Start the engine.
4 Operate the vehicle within the conditions for running the DTC.
Does any of the IAT sensor DTCs fail this ignition cycle? Go to Step 2 Go to Step 10
10 Using Tech 2, select the DTC display function.
Does Tech 2 display any DTCs? Go to the
appropriate DTC
Table in this Section System OK
When all diagnosis and repairs are completed, check the system for correct operation.
7.8 DTC P0116, P0117, P0118, P0125 or
P1258
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0116 – Engine Coolant Temperature Sensor Circuit Range / Performance
• DTC P0117 – Engine Coolant Temperature Sensor Circuit Low Voltage
• DTC P0118 – Engine Coolant Temperature Sensor Circuit High Voltage
• DTC P0125 – Insufficient Engine Coolant Temperature For Closed Loop Fuel Control
• DTC P1258 – Engine Coolant Over Temperature - Protection Mode Active
Circuit Description
The ECM applies a reference 5 V to the engine coolant temperature (ECT) sensor signal circuit and ground through the
low reference circuit. The ECT sensor is a variable resistor that measures the temperature of the engine coolant.
• Increased temperature in the engine coolant decreases the resistance value of the ECT sensor. This increases the
ECT sensor pull-down rate to ground. Therefore, the higher the engine coolant, the lower the signal voltage output
of the ECT sensor.
• Decreased temperature in the engine coolant increases the resistance value of the ECT sensor. This reduces the
ECT sensor pull-down rate to ground. Therefore, the lower the engine coolant temperature, the higher the signal
voltage output of the ECT sensor.
An ECT sensor DTC sets if the ECM detects the engine coolant temperature is outside the predetermined range.
Conditions for Running the DTC
DTC P0116
Runs continuously when the engine is running.
DTC P0117, P0118 and P1258
Runs continuously when the ignition is switched on.
DTC P00125
Runs continuously once the following conditions are met:
• DTCs P0112, P0113, P0117 or P0118 are not set.
• The engine is running.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–76

Conditions for Setting the DTC
DTC P0116
The ECM detects the engine coolant temperature sensor value is 10°C less than the minimum calculated engine
temperature.
DTC P0117
The ECM detects the engine coolant temperature is greater than 140 °C for longer than 3 seconds.
DTC P0118
The ECM detects the engine coolant temperature is less than -39 °C for longer than 3 seconds.
DTC P0125
The ECM determines the calculated engine temperature by measuring the amount of airflow into the engine. This DTC
sets if the ECM detects the actual ECT sensor is not within 10ºC of the calculated engine temperature for approximately
2 – 5 minutes.
DTC P1258
The ECM detects the engine coolant temperature is greater than 131 °C for longer than 2 seconds.
Conditions for Clearing the DTC
The ECT sensor DTCs are Type B DTCs. Refer to 1.4 Diagnostic Trouble Codes in this Section, for action taken when a
Type B DTC sets and conditions for clearing Type B DTC.
Additional Information
• Refer to 6C1-1 Engine Management – V6 – General Information for details of the ECT sensor operation.
• For an intermittent fault condition, refer to 5.2 Intermittent Fault Conditions in this Section.
• DTCs P0116, P0117, P0118 and P0125 diagnostic table is developed with the assumption the engine cooling
system is functioning correctly. Therefore, rectify any engine cooling system fault conditions before proceeding
with this diagnostic table.
• Test the ECT sensor using the ECT Temperature vs. Resistance in 6C1-3 Engine Management –V6 – Service
Operations. If the engine has sat overnight, the ECT sensor should display within 3 °C of the IAT sensor values.
W hen the engine is first started, the ECT should rise steadily to about 90 °C then stabilise when thermostat opens.
• Since fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic
procedure for shorted terminals or poor wiring connection before replacing any component. Refer to 8A Electrical -
Body and Chassis for information on electrical fault diagnosis.
• To assist diagnosis, refer to 3 W iring Diagrams and Connector Charts in this Section, for the system wiring
diagram and connector charts.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 A fault condition in the engine cooling system may trigger these DTCs.
7 The ECT sensor low reference circuit is shared with other components. DTC P0118 may set if the shared low reference circuit is shorted to voltage. Test the low reference circuit of all components that share this circuit to find
the source of the fault condition.
DTC P0116, P0117, P0118, P0125 and P1258 Diagnostic Table
Step Action Yes No
1 Has the Diagnostic System Check been performed?
Go to Step 2 Refer to
4.4 Diagnostic
System Check in this Section

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–84

• The calculated exhaust temperature is 250ºC – 800ºC.
• The engine coolant temperature is less than 40ºC at start-up and greater than 60ºC when the ignition was turned
off last ignition cycle.
• The fuel tank level is greater than 25 percent.
DTC P0138 and P0158
Run continuously once the following conditions are met:
• The engine is operating for longer than two minutes.
• The ignition voltage is 10.0 – 16.0 V.
• The HO2S is at operating temperature.
• The calculated exhaust temperature is 250ºC – 800ºC.
DTC P0140 and P0160
Run continuously once the following conditions are met for longer than 90 seconds:
• The engine is operating.
• The ignition voltage is 10.0 – 16.0 V.
• The calculated exhaust temperature is 250º C – 800º C.
DTC P0141 and P0161
Run continuously once the following conditions are met:
• DTCs P0036, P0037, P0038, P0056, P0057, and P0058 ran and passed.
• DTCs P0137, P0138, P0140, P0157, P0158, or P0160 are not set.
• The engine is operating.
• The ECM internal sensing element resistance is valid.
• The fuel system is not in decel fuel shut-off.
• The intake air temperature is greater than -7ºC.
• If the engine is operating and the ignition is turned off, the engine must be off for at least 5 minutes for this DTC to
run.
• The ignition voltage is 10.0 – 16.0 V.
• The calculated exhaust temperature is 360ºC – 500ºC.
DTC P2243 and P2247
Run continuously once the following conditions are met:
• DTCs P0030, P0031, P0032, P0050, P0051 and P0052 ran and passed.
• The ECM internal sensing element resistance is greater than 570 Ω.
• The HO2S is at operating temperature.
DTC P2270 and P2272
Run continuously once the following conditions are met:
• DTCs P0036, P0037, P0038, P0056, P0057, P0058, P0137, P0138, P0140, P0141, P0157, P0158, P0160, P0161,
P0342, P0343, P0443, P0458 and P0459 ran and passed.
• The engine is running.
• The HO2S 2 are at operating temperature for longer than 10 seconds.
• The long term fuel control is enabled.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–91

Step Action Yes No
7 NOTE
If both DTCs are set, determine and correct the cause of
the contamination before replacing a sensor.
1 Inspect for the following conditions:
• Fuel contamination – refer to 6.5 Alcohol / Contaminants
in Fuel Diagnosis in this Section.
• The correct RTV sealant.
• Engine oil consumption – refer to 6A1 Engine Mechanical
– V6.
• Engine coolant consumption – refer to 6B1 Engine Cooling
– V6.
2 Replace the HO2S. Refer to 6C1-3 Engine Management – V6 – Service Operations.
Did you complete the replacement? Go to Step 8 —
8 1 Use Tech 2 to Clear the DTCs.
2 Turn OFF the ignition for 30 seconds.
3 Start the engine.
4 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 2 Go to Step 9
9 1 Using Tech 2, select the DTC display function.
Does Tech 2 display any DTCs? Go to the
appropriate DTC
Table in this Section System OK
When all diagnosis and repairs are completed, clear all DTCs and verify correct operation
7.12 DTC P0139 or P0159
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0139 – O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)
• DTC P0159 – O2 Sensor Circuit Slow Response (Bank 2 Sensor 2)
Circuit Description
The post catalytic converter heated oxygen sensor (HO2S) produces a voltage that varies between 100 – 900 mV under
normal operating conditions. The engine control module (ECM) produces a bias voltage on the HO2S signal circuit of
420 – -480 mV. The reference ground for the sensor is provided through the ECM.
The ECM monitors the signal voltage to determine if the exhaust is lean or rich. The oxygen sensor voltage is high when
the exhaust is rich, and low when the exhaust is lean. The ECM constantly monitors the HO2S signal during the Closed
Loop operation. If the ECM detects that the decel fuel cut-off rich-to-lean transition time is too long, DTC P0139 will set
for bank 1 sensor 2, or DTC P0159 will set for bank 2 sensor 2.
Conditions for Running the DTC
• DTCs P0021, P0024, P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0056, P0057, P0058,
P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0121, P0122, P0123, P0125, P0128,
P0131, P0132, P0135, P0137, P0138, P0139, P0140, P0141, P0151, P0152, P0155, P0157, P0158, P0159,
P0160, P0161, P0201-P0208, P0221, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270,
P0271, P0273, P0274, P0276, P0277, P0279, P0280, P0282, P0283, P0300, P0301-P0308, P0335, P0336,

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–106

− Damaged accessory drive belt
• For an intermittent condition, refer to 5.2 Intermittent Fault Conditions in this Section.
• Since a fault condition in a wiring connector may trigger DTCs, always test the connectors related to this
diagnostic procedure for shorted terminals or poor wiring connection before replacing any component. Refer to 8A
Electrical - Body and Chassis for information on electrical fault diagnosis.
• To assist diagnosis, refer to 3 W iring Diagrams and Connector Charts in this Section, for the system wiring
diagram and connector charts.
DTC P0301, P0302, P0303, P0304, P0305 or P0306 Diagnostic Table
Step Action Yes No
1
Has the Diagnostic System Check been completed? Go to Step 2 Refer to
4.4 Diagnostic
System Check in this Section
2
W ere you sent here from DTC P0300? Go to Step 3 Go to 7.16
DTC P0300 in this Section
3 1 Ignition OFF.
2 Remove the ignition coil of the misfiring cylinder, but leave the electrical connector connected. Refer to 6C1-3 Engine
Management – V6 – Service Operations.
3 Inspect the ignition coil boot for the following conditions:
− Holes.
− Tears.
− Carbon tracking.
− Oil contamination or water intrusion.
Did you find a condition with the ignition coil boot? Go to Step 12 Go to Step 4
4 1 Remove the fuel pump fuse from the under-hood fuse and relay
centre.
2 Install the J 26792 Spark Tester to the ignition coil boot and a good ground.
3 Crank the engine while observing J 26792.
Does the spark tester spark and is the spark consistent? Go to Step 5 Go to Electronic
Ignition System Diagnosis
5 1 Ignition OFF.
2 Remove the spark plug from the cylinder that indicated a misfire.
3 Inspect the spark plug. Refer to 6C1-3 Engine Management – V6 – Service Operations.
Does the spark plug appear to be OK? Go to Step 9 Go to Step 6
6
Is the spark plug oil or coolant fouled? Inspect the spark
plugs. Go to 6C1-3 Engine
Management – V6 – Service Operations Go to Step 7
7 Is the spark plug gas fouled? Go to Step 10 Go to Step 9
8 Does the spark plug show any signs of being cracked, worn, or
incorrectly gap? Go to Step 11 Go to Step 9

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–108

Test One
The ECM performs the following:
1 Turns off the knock sensor signal circuits.
2 Applies different test signals to the ECM internal KS circuitry.
3 Verifies each test signal output response is within range.
4 If the ECM detects any of the tested signals are not within the normal range, DTC P0324 sets.
Test Two
The ECM performs the following:
1 Turns off the knock sensor signal circuits.
2 Tests for any output response when no test signals are applied.
3 If the ECM detects an output response, DTC P0324 sets.
Test Three
1 Turns off the knock sensor signal circuits.
2 Generates an internal test pulse then monitors the return signal.
3 If the return test pulse is less than a calibrated threshold, DTC P0324 sets.
DTC P0324 sets if the ECM detects an incorrect response to the ECM internal KS circuitry tests.
Conditions for Running the DTC
Condition One
Runs continuously once the following conditions are met:
• The ECM is controlling the ignition spark.
• The engine speed is less than 2,300 rpm and steady.
• The volumetric efficiency is steady.
Condition Two
Runs continuously once the following conditions are met:
• The ECM is controlling the ignition spark.
• The engine speed is 1,000 – 4,000 rpm
• The engine coolant temperature is greater than 60 ° C.
• The volumetric efficiency is steady.
Condition Three
Runs continuously once the following conditions are met:
• The ECM is controlling the ignition spark.
• The engine speed is less than 2,300 rpm and steady.
• The engine coolant temperature is greater than 40 ° C.
• The volumetric efficiency is steady.
Conditions for Setting the DTC
The ECM detects an incorrect response to an internal ECM KS circuitry test.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Engine Management – V6 – Diagnostics Page 6C1-2–110

7.19 DTC P0327, P0328, P0332 or P0333
DTC Descriptor
This diagnostic procedure supports the following DTCs:
• DTC P0327 – Knock Sensor Circuit Low Frequency (Bank 1)
• DTC P0328 – Knock Sensor Circuit High Frequency (Bank 1)
• DTC P0332 – Knock Sensor Circuit Low Frequency (Bank 2)
• DTC P0333 – Knock Sensor Circuit High Frequency (Bank 2)
Circuit Description
The ECM supplies the ground to the knock sensor (KS) low reference circuit. The KS produces a signal voltage, which is
proportional to the level of the engine vibration or spark knock.
W hen the ECM detects an excessive spark knock, it retards the ignition timing until the spark knock stops.
To differentiate between a normal engine vibration and the vibration created by a spark knock, the ECM samples the KS
signal under different engine speeds and load condition. The ECM uses this samples to determine maximum and
minimum KS signal voltage produced when the engine is running under normal conditions.
A knock sensor circuit DTC sets if the ECM detects the KS signal voltage is outside the normal range.
Conditions for Running the DTC
DTC P0327 and P0332
Run continuously once the following conditions are met:
• DTCs P0324, P0335, P0342 and P0343 ran and passed.
• The ECM controls the ignition spark.
• Engine speed is greater than 2000 rpm and steady.
• The engine coolant temperature is greater than 60ºC.
• The volumetric efficiency is steady.
DTC P0328 or P0333
Run continuously once the following conditions are met:
• The ECM controls the ignition spark.
• Engine speed is greater than 2,000 rpm and steady.
• The engine coolant temperature is greater than 60 °C.
• The volumetric efficiency is steady.
Conditions for Setting the DTC
DTC P0327 and P0332
The ECM detects the KS signal voltage is less than the minimum KS signal normal range for at least 10 seconds.
DTC P0328 and P0333
The ECM detects the KS signal voltage is greater than the maximum KS signal normal range.
Conditions for Clearing DTC
The knock sensor circuit DTCs are Type B DTCs. Refer to 1.4 Diagnostic Trouble Codes in this Section, for action
taken when Type B DTC sets and conditions for clearing Type B DTCs.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007