Circuit Description
The camshaft position PCM input is produced by the ignition control module or ICM. The ICM produces the camshaft position PCM input by filtering the camshaft position (CMP) sensor pulses when the engine is running and CKP sync pulses are also being received. The PCM uses the camshaft position PCM input pulses to initiate sequential fuel injection and to determine crankshaft position for the misfire diagnostic. The PCM constantly monitors the number of pulses on the camshaft position PCM input circuit and compares the number of camshaft position PCM input pulses to the number of 18X reference pulses and the number of 3X reference pulses being received. If the PCM receives an incorrect number of pulses on the camshaft position PCM input circuit, DTC P0341 will set and the PCM will initiate injector sequence without the camshaft position PCM input with a one in six chance that injector sequence is correct. The engine will continue to start and run normally, although the misfire diagnostic will be disabled.
Conditions for Running the DTC
The engine is running (3X reference pulses are being received).
Conditions for Setting the DTC
No cam sensor reference pulses are not received in one engine cycle (720 degrees of crankshaft rotation).
Action Taken When the DTC Sets
| • | The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed. |
| • | The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data. |
Conditions for Clearing the MIL/DTC
| • | The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed. |
| • | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The DTC can be cleared by using a scan tool. |
Diagnostic Aids
Inspect for the following:
| • | Secondary ignition wires arcing to wiring harness - Inspect secondary ignition wires for carbon tracking or other signs of damage. |
| • | Faulty Ignition Coil - Remove the ignition coils and inspect the ignition control module and coils for cracks, carbon tracking, or other signs that indicate that the coil secondary circuit is arcing to the ICM or ICM wiring harness. Refer to Ignition Coil Replacement . |
Many situations may lead to an intermittent condition. Perform each inspection or test as directed.
Important: : Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
| • | Loose terminal connection |
| - | Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| - | Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair. |
| • | Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
| • | Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair. |
If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Ensures that the fault is present.
-
Determines whether the fault is caused by a missing camshaft magnet or a faulty PCM. The voltage measured in this step should read around 4 volts, toggling to near 0 volts when the CMP sensor interfaces with the camshaft magnet.
-
This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
1 |
Important:: If the engine cranks but will not run, refer to Engine Cranks but Does Not Run . Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||||||
Operate vehicle within Fail Records conditions. Does the scan tool indicate this DTC failed this ignition? | -- | Go to Diagnostic Aids | ||||||
3 |
Important: If voltage measures 0, bump over engine to insure cam sensor magnet is not located under the cam sensor at the time of this test. Does the voltage measure near the specified value? | 5V | ||||||
4 |
Important:
Does the voltage toggle from 5 volts to 0 volts as the magnet is placed on the sensor? | -- | ||||||
5 | Does the voltage on the camshaft position input signal circuit measure more than the specified value? | 5V | ||||||
6 |
Did you find and correct the condition? | -- | ||||||
7 |
Did you find and correct the condition? | -- | ||||||
8 |
Is the voltage at the specified value? | B+ | ||||||
9 | Measure the voltage on the CMP sensor signal circuit using a DMM that is connected to the CMP ground circuit. Does the voltage measure within the specified range? | 5-7V | ||||||
10 |
Does the voltage switch between 0 and 5 volts when the test lamp is repeatedly touched to the CMP signal circuit? | -- | ||||||
11 | Test for the following conditions:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||
12 | Test the following circuits for an open between the ICM and the CMP sensor:
Refer to Circuit Testing and Wiring Repairs in Wiring Systems Did you find and correct the condition? | -- | ||||||
13 | Test for an open in the camshaft position input signal circuit between the PCM and the ICM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||
14 | Inspect for poor connections at the ICM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||
15 | Inspect for poor connections at the CMP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||
16 | Inspect for poor connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||
17 | Inspect for the following conditions:
Did you find and correct the condition? | -- | ||||||
18 | Replace the ICM. Refer to Ignition Control Module Replacement . Did you complete the replacement? | -- | -- | |||||
19 | Replace the CMP sensor. Refer to Camshaft Position Sensor Replacement . Did you complete the replacement? | -- | -- | |||||
20 | Inspect for the following conditions:
Did you find and correct the condition? | -- | ||||||
Does the voltage toggle between the specified values? | 5V / 0V | |||||||
|
Important:: The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming . Did you complete the replacement? | -- | -- | ||||||
23 | Replace faulty or missing CMP sensor magnet. Did you complete the replacement? | -- | -- | |||||
24 |
Does the DTC reset? | -- | System OK |
