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Engine Management – V6 – Diagnostics Page 6C1-2–115
Step Action Yes No
8 Repair the open or high resistance fault condition in the CKP sensor
ground shield circuit. Refer to 8A Electrical - Body and Chassis for
information on electrical repair procedures.
W as the repair completed? Go to Step 11 —
9 Replace CKP sensor. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 11 —
10 Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 11 —
11 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 CKP sensor circuit DTCs fail this ignition cycle? Go to Step 2 Go to Step 12
12 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.
7.21 DTC P0341, P0342 or P0343
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0341 – Intake Camshaft Position Sensor Range / Performance (Bank 1)
• DTC P0342 – Intake Camshaft Position Sensor Low Voltage (Bank 1)
• DTC P0343 – Intake Camshaft Position Sensor High Voltage (Bank 1)
Circuit Description
The ECM applies 5 V to the camshaft position (CMP) sensors through the 5 V reference and ground through the low
reference circuit.
The CMP sensor is a Hall effect switch. In conjunction with a 4X reluctor wheel, the CMP sensors provide a signal
voltage to the ECM. The ECM uses this signal voltage to determine the position of the camshafts.
The ECM compares the CMP signal voltage to the number of crankshaft revolutions. A CMP sensor DTC sets if the
ECM detects a fault condition in the CMP sensor circuits.
Conditions for Running the DTC
The engine is running.
Conditions for Setting the DTC
DTC P0342
The ECM detects no pulses from the CMP sensor signal circuit and the CMP sensor signal voltage is low in correlation
with the number of crankshaft revolutions.
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Engine Management – V6 – Diagnostics Page 6C1-2–116
DTC P0341
The ECM detects a signal from the CMP sensor signal circuit and the sensor signal range is not within the
predetermined parameter or the when the CMP sensor does not correlate with the crankshaft position.
DTC P0343
The ECM detects no pulses from the CMP sensor signal circuit and the CMP sensor signal voltage is always high.
Conditions for Clearing the DTC
The CMP sensor circuit 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 sensor operation.
• 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 Tests the signal circuit of the CMP sensor. This circuit is pulled-up to about 5 V.
4 Measures the integrity of the CMP sensor low reference circuit. Removal of the ECM Fuse 29 enables the ECM to power down completely prior to the test procedure.
DTC P0341, P0342 or P0343 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
2 1 Switch off the ignition for 30 seconds.
2 Start the engine.
3 Increase the engine speed to 1000 rpm for 30 seconds.
4 Using Tech 2, select the DTC display function.
Does P0341, P0342, P0343 fail this ignition cycle? Go to Step 3 Refer to Additional
Information in this DTC
3 1 Switch off the ignition.
2 Disconnect the appropriate CMP sensor wiring connector.
3 Switch on the ignition with the engine not running.
4 Using a digital multimeter, measure the voltage between the signal circuit of the appropriate CMP sensor and the ECM
housing.
Does the multimeter display 4.8 – 5.2 V? Go to Step 4 Go to Step 7
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Engine Management – V6 – Diagnostics Page 6C1-2–117
Step Action Yes No
4 1 Switch off the ignition.
2 Remove ECM Fuse 29 from the engine compartment fuse and relay panel assembly.
3 Using a digital multimeter, measure the resistance between the CMP sensor low reference circuit and the ECM housing.
NOTE
Install the ECM Fuse 29 to the engine compartment fuse
and relay panel assembly after completing this test.
Does the multimeter display 5 Ω?
Go to Step 5 Go to Step 8
5 Test the signal circuit of the CMP sensor for a high resistance, open
circuit, short to ground or short to voltage fault condition. Refer to 8A
Electrical - Body and Chassis for information on electrical fault
diagnosis.
W as any fault found and rectified? Go to Step 11 Go to Step 6
6 Perform the following CMP sensor inspection:
• Inspect the sensor wiring harness for conditions that may induce
electromagnetic interference. Refer to
5.2 Intermittent Fault Conditions in this Section.
• Inspect the sensor for incorrect sensor installation or incorrect
attaching bolt torque value. Refer to 6C1-3 Engine Management
– V6 – Service Operations.
• Inspect the CMP sensor reluctor wheel for damage or conditions
that causes misalignment.
W as any fault found and rectified? Go to Step 11 Go to Step 9
7 Test the CMP sensor 5 V reference circuit for a high resistance, open
circuit, short to voltage or short to ground fault condition. Refer to 8A
Electrical - Body and Chassis for information on electrical fault
diagnosis.
NOTE
Each CMP sensor shares a common 5 V reference circuit.
A fault condition in the 5 V reference circuit may trigger
DTCs on all CMP sensors. Refer to 3 W iring Diagrams
and Connector Charts in this Section, to assist diagnosis.
W as any fault found and rectified? Go to Step 11 Go to Step 10
8 Test the CMP sensor low reference circuit for a high resistance or an
open circuit fault condition. Refer to 8A Electrical - Body and Chassis
for information on electrical fault diagnosis.
NOTE
The CMP sensor shares the low reference circuit with
other sensors. A fault condition in the low reference circuit
may trigger DTCs on sensors that share this circuit. Refer
to 3 W iring Diagrams and Connector Charts in this
Section, to aid diagnosis.
W as any fault found and rectified? Go to Step 11 Go to Step 10
9 Replace the appropriate CMP sensor. Refer to 6C1-3 Engine
Management – V6 – Service Operations.
W as the repair completed? Go to Step 11 —
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Engine Management – V6 – Diagnostics Page 6C1-2–118
Step Action Yes No
10 Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 11 —
11 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 CMP Sensor Circuit DTCs fail this ignition cycle? Go to Step 2 Go to Step 12
12 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.
7.22 DTC P0351, P0352, P0353, P0354, P0355,
P0356, P2300, P2301, P2303, P2304,
P2306, P2307, P2309, P2310, P2312,
P2313, P2315 or P2316
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0351 – Ignition Coil Cylinder 1 Circuit Malfunction
• DTC P0352 – Ignition Coil Cylinder 2 Circuit Malfunction
• DTC P0353 – Ignition Coil Cylinder 3 Circuit Malfunction
• DTC P0354 – Ignition Coil Cylinder 4 Circuit Malfunction
• DTC P0355 – Ignition Coil Cylinder 5 Circuit Malfunction
• DTC P0356 – Ignition Coil Cylinder 6 Circuit Malfunction
• DTC P2300 – Ignition Coil Cylinder 1 Circuit Low Voltage
• DTC P2301 – Ignition Coil Cylinder 1 Circuit High Voltage
• DTC P2303 – Ignition Coil Cylinder 2 Circuit Low Voltage
• DTC P2304 – Ignition Coil Cylinder 2 Circuit High Voltage
• DTC P2306 – Ignition Coil Cylinder 3 Circuit Low Voltage
• DTC P2307 – Ignition Coil Cylinder 3 Circuit High Voltage
• DTC P2309 – Ignition Coil Cylinder 4 Circuit Low Voltage
• DTC P2310 – Ignition Coil Cylinder 4 Circuit High Voltage
• DTC P2312 – Ignition Coil Cylinder 5 Circuit Low Voltage
• DTC P2313 – Ignition Coil Cylinder 5 Circuit High Voltage
• DTC P2315 – Ignition Coil Cylinder 6 Circuit Low Voltage
• DTC P2316 – Ignition Coil Cylinder 6 Circuit High Voltage
Circuit Description
The engine control relay applies positive voltage to the ignition voltage circuit of the ignition coil and the ignition coil du al
line ground circuits are directly connected to ground.
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Engine Management – V6 – Diagnostics Page 6C1-2–119
The ECM applies control voltage to the control circuit of the ignition coil during the calculated dwell period that allows
current flow to the ignition coil primary winding to generate a magnetic flux field. At the appropriate firing point, the ECM
interrupts the control voltage applied to the ignition coil.
Interruption of voltage applied to the control circuit of the ignition coil primary winding induces the transfer of electrical
energy from the ignition coil primary winding to the ignition coil secondary winding, which triggers the ignition coil to
produce a spark at the spark plug.
An ignition coil control circuit DTC sets if the ECM detects a fault condition in the control circuit of an ignition coil.
Conditions for Running the DTC
Run continuously once the following conditions are met:
• The engine is running.
• The engine speed is 480 – 5,000 rpm
• The battery voltage is 10.0 – 16.0 V.
Conditions for Setting the DTC
DTC P0351, P0352, P0353, P0354, P0355 or P0356
The ECM detects an open circuit fault condition in the ignition coil control circuit.
DTC P2300, P2303, P2306, P2309, P2312 or P2315
The ECM detects a short to ground fault condition in the ignition coil control circuit.
DTC P2301, P2304, P2307, P2310, P2313 and P2316
The ECM detects a short to voltage fault condition in the ignition coil control circuit.
Conditions for Clearing the DTC
The ignition coil control 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.
Additional Information
• Refer to 6C1-1 Engine Management – V6 – General Information for details of the ignition coil operation.
• A short to voltage fault condition damages the ignition coil. Do not replace the ignition until this fault condition is
rectified.
• The ignition coils for each bank of the engine are fused separately. If all DTCs for a single bank are set, there may
be a fault in one of the ignition supply circuits.
• The ignition coils for each bank of the engine have a separate ground connections. If all DTCs for a single bank
are set, there may be a fault in one of the ground circuits.
• 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 Determines if there is a fault condition in the ignition voltage supply circuit.
5 Determines if there is a fault condition in the ground circuits of the ignition coil.
6 Tests if the ECM is commanding the ignition coil on and off.
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Engine Management – V6 – Diagnostics Page 6C1-2–120
DTC P0351 to P0356, P2300, P2301, P2303, P2304, P2306, P2307, P2309, P2310, P2312,
P2313, P2315 or P2316 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
2 1 Switch off the ignition for 30 seconds.
2 Start the engine.
3 Using Tech 2, select the DTC display function.
Does DTC P0351, P0352, P0353, P0354, P0355, P0356, P2300,
P2301, P2303, P2304, P2306, P2037, P2309, P2310, P2312, P2313,
P2315 or P2316 fail this ignition cycle? Go to Step 3 Refer to Additional
Information in this DTC
3 1 Disconnect the wiring connector of the appropriate ignition coil.
2 Switch on the ignition with the engine not running.
3 Connect a test lamp between the ignition voltage circuit of the appropriate ignition coil connector and the ECM housing.
Does the test lamp illuminate? Go to Step 4 Go to Step 6
4 Connect a test lamp between a 12 V and each of the ground circuits
of the ignition coil connector.
Does the test lamp illuminate? Go to Step 5 Go to Step 7
5 1 Start the engine.
2 Using a digital multimeter, measure the frequency at the control circuit of the ignition coil.
Does the multimeter display 3 – 20 Hz? Go to Step 9 Go to Step 8
6 Repair the high resistance or open circuit fault condition at the ignition
voltage circuit of the ignition coil. Refer to 8A Electrical - Body and
Chassis for information on electrical wiring repair procedures.
W as the repair completed? Go to Step 11 —
7 Repair the high resistance or open circuit fault condition at the ignition
coil ground circuits. Refer to 8A Electrical - Body and Chassis for
information on electrical wiring repair procedures.
W as the repair completed? Go to Step 11 —
8 Test the appropriate ignition coil control circuit for a high resistance,
open circuit, short to ground or short to voltage fault condition. Refer
to 8A Electrical - Body and Chassis for information on electrical fault
diagnosis.
W as any fault found and rectified? Go to Step 11 Go to Step 10
9
A short to voltage fault condition damages the ignition
coil. Do not replace the ignition until this fault
condition is rectified.
Replace the faulty ignition coil. Refer to 6C1-3 Engine Management –
V6 – Service Operations.
W as the repair completed? Go to Step 11 —
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Engine Management – V6 – Diagnostics Page 6C1-2–121
Step Action Yes No
10 Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.
W as the repair completed? Go to Step 11 —
11 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 ignition coil control circuit DTCs fail this ignition
cycle? Go to Step 2 Go to Step 12
12 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.
7.23 DTC P0420 or P0430
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC P0420 Catalyst System Low Efficiency Bank 1
• DTC P0430 Catalyst System Low Efficiency Bank 2
Circuit Description
To maintain a reasonably low emission level of hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen
(NOx) a 3-way catalytic converter (TW C) is used. The catalyst within the converter promotes a chemical reaction that
oxidizes the HC and CO present in the exhaust gas. This reaction converts the gases into harmless water vapour and
carbon dioxide. The catalyst also reduces the NOx, converting the NOx into nitrogen. The engine control module (ECM)
monitors this process using the post catalyst heated oxygen sensor (HO2S) signal. The post-catalyst HO2S located in
the exhaust stream after the TW C, produces an output signal that indicates the oxygen storage capacity of the catalyst.
The oxygen storage capacity (OSC) determines the ability of the catalyst to convert the exhaust emissions effectively. If
the catalyst is functioning correctly, the post-catalyst HO2S signal will be far less active than the signal produced by the
pre-catalyst HO2S.
To determine OSC, the ECM commands a rich air / fuel mixture until all oxygen is removed from the catalyst. The ECM
then commands a lean air / fuel mixture and monitors the rear heated oxygen sensors to calculate the oxygen storage
capacity. The catalyst is operated in this mode until one of the following conditions occur:
• The oxygen stored in the catalyst exceeds a calibrated threshold, which is determined from the rear HO2S signal.
• The rear HO2S indicates the catalyst to be completely saturated with oxygen, which is determined from the rear
HO2S signal.
If the ECM detects the average OSC is less than a threshold, this DTC sets. This indicates that the TW C oxygen
storage capacity is below a threshold considered acceptable.
Conditions for Running the DTC
• Before the ECM can report, the following DTCs must run and pass:
DTC P0420 or P0430 failed, DTCs P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0053,
P0056, P0057, P0058, P0059, P0101, P0102, P0103, P0121, P0122, P0123, P0130, P0131, P0132, P0133,
P0135, P0137, P0138, P0139, P0140, P0141, P0150, P0151, P0152, P0153, P0155, P0157, P0158, P0159,
P0160, P0161, P0221, P0222, P0223, P0335, P0336, P0338, P167A, P167B, P2096, P2097, P2098, P2099,
P2195, P2196, P2197, P2198, P2232, P2235, P2237, P2240, P2243, P2247, P2251, P2254, P2270, P2271,
P2272, P2273, P2297, P2298, P2626, and P2629.
• The following DTCs are not set:
DTCs P0030, P0031, P0032, P0036, P0037, P0038, P0050, P0051, P0052, P0053, P0056, P0057, P0058,
P0059, P0101, P0102, P0103, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0125, P0130, P0131,
P0132, P0133, P0135, P0137, P0138, P0139, P0140, P0141, P0150, P0151, P0152, P0153, P0155, P0157,
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Engine Management – V6 – Diagnostics Page 6C1-2–122
P0158, P0159, P0160, P0161, P0221, P0222, P0223, P0300, P0301-P0306, P0443, P0458, P0459, P0496,
P167A, P167B, P2096, P2097, P2098, P2099, P2100, P2101, P2107, P2119, P2122, P2123, P2127, P2128,
P2138, P2176, P2177, P2178, P2179, P2180, P2187, P2188, P2189, P2190, P2195, P2196, P2197, P2198,
P2232, P2235, P2237, P2240, P2243, P2247, P2251, P2254, P2270, P2271, P2272, P2273, P2297, P2298,
P2626, and P2629.
• The engine speed is 1,040 – 3,000 rpm.
• The air flow into the engine is between 7.0 – 16.0 g/s and not changing more than 3.0 g/s
• The engine intake air temperature (IAT) at engine start-up is more than –30° C.
• The engine is operating for more than 7 minutes.
• The engine is operating in Closed Loop.
• The calculated TW C temperature is between 500 – 750° C and steady.
• The above conditions exist for approximately 17 minutes.
• DTCs P0420 and P0430 run once a drive cycle. The ECM will attempt to run this diagnostic up to three times a
drive cycle.
Conditions for Setting the DTC
The ECM determines that the catalyst efficiency has degraded below a calibrated threshold for more than 4 seconds.
Action Taken When the DTC Sets
• The control module activates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that
the diagnostic runs and fails.
• The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic
fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the
second consecutive ignition cycle, the control module records the operating conditions at the time of the failure.
The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
Conditions for Clearing the DTC
The EVAP Purge Solenoid Valve Control Circuit 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 DTCs.
P0420 or P0430 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 Are any other DTCs set? Go to the
appropriate DTC
Table in this Section Go to Step 3
3 1 Inspect for the following conditions:
• The catalytic converter is an original equipment part.
• Inspect the exhaust system for leaks, damage, loose or
missing hardware in the area from the converter to the
heated oxygen sensor 2.
• The HO2S 2 is secure and the wiring is not damaged or
contacting the exhaust.
Did you find and correct the condition? Go to Step 5 Go to Step 4
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