DTC P0341 Camshaft Position (CMP)
Sensor Performance
Circuit
Description
The Camshaft Position
sensor is mounted through the top of the engine block at the rear of the valley
cover. The CMP sensor works in conjunction with a 1X reluctor
wheel on the camshaft. The reluctor wheel is inside
the engine immediately in front of the rear cam bearing. The PCM provides a 12
volt power supply to the CMP sensor as well as a ground and a signal circuit.
The CMP sensor
determines whether a cylinder is on a firing stroke or on an exhaust stroke. As
the camshaft rotates, the reluctor wheel interrupts a
magnetic field produced by a magnet within the sensor. The sensors internal
circuitry detects this and produces a signal which the PCM reads. The PCM uses
this 1X signal in combination with the Crankshaft Position sensor 24X signal in
order to determine crankshaft position and stroke. This diagnostic for the
Camshaft Position sensor tests for a loss of Camshaft Position sensor signal.
Observe that as long as
the Crankshaft Position sensor 24X signal is available, the engine will start.
The PCM can determine top dead center for all cylinders by using the Crankshaft
Position sensor 24X signal alone. The Camshaft Position sensor 1X signal is
used by the PCM to determine if the cylinder at top dead center is on the
firing stroke, or the exhaust stroke. The system attempts synchronization and
looks for an increase in engine speed indicating the engine started. If the PCM
does not detect an increase in engine speed, the PCM incorrectly synchronized
to the exhaust stroke and will re-sync to the opposite cam position. A slightly
longer cranking time may be a symptom of this condition.
Conditions
for Running the DTC
- The ignition voltage is between
5.0 volts and 17.0 volts.
- The engine speed is less than
4,000 RPM.
Conditions
for Setting the DTC
The PCM detects that a
CMP to CKP mis-match has occurred for 10 second.
Action
Taken When the DTC Sets
- The PCM illuminates the malfunction indicator
lamp (MIL) on the second consecutive ignition cycle that the diagnostic
runs and fails.
- The PCM records the operating
conditions at the time the diagnostic fails. The first time the diagnostic
fails, the PCM stores this information in the Failure Records. If the
diagnostic reports a failure on the second consecutive ignition cycle, the
PCM records the operating conditions at the time of the failure. The PCM
writes the conditions to the Freeze Frame and updates the Failure Records.
Conditions
for Clearing the MIL/DTC
- The PCM turns OFF the malfunction
indicator lamp (MIL) after 3 consecutive ignition cycles that the
diagnostic runs and does not fail.
- A last test failed, or current DTC,
clears when the diagnostic runs and does not fail.
- A history DTC clears after
40 consecutive warm-up cycles, if no failures are reported by this or
any other emission related diagnostic.
- Use a scan tool in order to clear
the MIL and the DTC.
Diagnostic
Aids
Important
- Remove any debris from the PCM connector surfaces
before servicing the PCM. Inspect the PCM connector gaskets when
diagnosing/replacing the PCM. Ensure that the gaskets are installed
correctly. The gaskets prevent contaminate intrusion into the PCM.
- For any test that requires probing the PCM or a
component harness connector, use the Connector Test Adapter Kit J 35616-A .
Using this kit prevents damage to the harness connector terminals.
- The following mechanical conditions
may cause this DTC to set:
- Using Freeze Frame and/or Failure Records
data may aid in locating an intermittent condition. If you cannot
duplicate the DTC, the information included in the Freeze Frame and/or
Failure Records data can aid in determining how many miles since the DTC
set. The Fail Counter and Pass Counter can also aid determining how many
ignition cycles the diagnostic reported a pass and/or a fail. Operate the
vehicle within the same freeze frame conditions (RPM, load, vehicle speed,
temperature etc.) that you observed. This will isolate when the DTC failed.
- For an intermittent, refer to Symptoms
.
Test
Description
The numbers below refer
to the step numbers on the diagnostic table.
- This step verifies
that the malfunction is present.
- This step tests for
EMI (Electro Magnetic Interference) on the CMP sensor circuits.
- Vertical lines
across the face of the sensor could indicate foreign material passing
between the CMP sensor and the reluctor
wheel. This condition would cause this DTC to set.
- Damage to the reluctor wheel would affect the
CMP sensor output. If this condition exists, refer to Camshaft
Replacement in Engine Mechanical 5.7L.
Step
|
Action
|
Value(s)
|
Yes
|
No
|
1
|
Did
you perform the Powertrain On-Board Diagnostic
(OBD) System Check?
|
--
|
Go
to Step 2
|
Go to A
Powertrain On Board Diagnostic (OBD) System Check
|
2
|
- Install a scan tool.
- Idle the engine for 2 minutes.
Does
the scan tool indicate that DTC P0341 failed this ignition?
|
--
|
Go
to Step 3
|
Go to Diagnostic Aids
|
3
|
- Visually/Physically inspect all
circuits going to the Camshaft Position sensor for the following:
- Routed to close to secondary
ignition wires or components
- Routed to close to after-market
add on electrical equipment
- Routed to close to solenoids,
relays and motors
- If you find incorrect routing,
correct the harness routing
Did
you find and correct the condition?
|
--
|
Go
to Step 9
|
Go
to Step 4
|
4
|
- Test the terminal contact at the
PCM for the CMP sensor circuits. Refer to Intermittents and Poor Connections Diagnosis in
Wiring Systems.
- If you find a poor connection,
repair as necessary. Refer to Repairing
Connector Terminals in Wiring Systems.
Did
you find and correct the condition?
|
--
|
Go
to Step 9
|
Go
to Step 5
|
5
|
- Remove the Intake Manifold. Refer
to Intake
Manifold Replacement in Engine Mechanical 5.7L.
- Test the terminal contact at the
CMP sensor. Refer to Intermittents and Poor Connections Diagnosis in
Wiring Systems.
- If you find a poor connection,
repair as necessary. Refer to Repairing
Connector Terminals in Wiring Systems.
Did
you find and correct the condition?
|
--
|
Go
to Step 9
|
Go
to Step 6
|
6
|
- Remove the CMP sensor. Refer to Camshaft
Position (CMP) Sensor Replacement .
- Inspect the CMP sensor for signs
of damage.
Did
you find the CMP sensor damaged?
|
--
|
Go to Camshaft
Replacement in Engine Mechanical 5.7L.
|
Go
to Step 7
|
7
|
Inspect
the CMP reluctor wheel for damage. Did you find the
CMP reluctor wheel damaged?
|
--
|
Go to Camshaft
Replacement in Engine Mechanical 5.7L.
|
Go
to Step 8
|
8
|
Replace
the CMP sensor. Refer to Camshaft
Position (CMP) Sensor Replacement . Is the action complete?
|
--
|
Go
to Step 9
|
--
|
9
|
- Select the Diagnostic Trouble Code
(DTC) option and the Clear DTC option using the scan tool.
- Idle the engine at the normal
operating temperature.
- Select the Diagnostic Trouble Code
(DTC) option and the Specific DTC option, then
enter the DTC number using the scan tool.
- Operate vehicle within the
Conditions for Running the DTC as specified in the supporting text, if
applicable.
Does
the scan tool indicate that this test ran and passed?
|
--
|
Go
to Step 10
|
Go
to Step 2
|
10
|
Select
the Capture Info option and the Review Info option using the scan tool. Does
the scan tool display any DTCs that you have not diagnosed?
|
--
|
Go to applicable DTC
table
|
System OK
|