Circuit Description
The camshaft position (CMP) sensor works in conjunction with a single tooth reluctor wheel on the Bank 2 Intake camshaft. The ECM pulls up the CMP sensor signal circuit to 5 volts and monitors this voltage. As the reluctor wheel tooth rotates past the sensor, the sensor's internal circuitry pulls the signal circuit to ground, creating a square wave signal that is used by the ECM. The reluctor wheel tooth covers 180 degrees of the camshaft circumference. This causes the CMP signal voltage to transition once per crankshaft revolution. This signal, when combined with the CKP sensor signal, enables the ECM to determine exactly which cylinder is on a firing stroke. The ECM can then properly synchronize the ignition system, the fuel injectors and the knock control. Note that as long as the CKP signal is available, the engine can start even if there is no CMP sensor signal. The ECM will default to a non-sequential fuel injector operation.
Conditions for Running the DTC
Engine Running.
Conditions for Setting the DTC
The CMP signal is not rational.
Action Taken When the DTC Sets
The ECM illuminates the malfunction indicator lamp (MIL) and records the operating conditions in the Freeze Frame on the second consecutive drive trip that the diagnostic runs and fails.
Conditions for Clearing the MIL/DTC
| • | The ECM turns OFF the MIL after three consecutive drive trips that the diagnostic runs and passes. |
| • | A History DTC clears after forty consecutive warm-up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic. |
| • | The ECM battery voltage is interrupted. |
| • | The scan tool clears the MIL/DTC. |
Diagnostic Aids
This DTC may set with an intermittently open shielded ground circuit. A completely open shielded ground circuit should set DTC P0340.
Notice: Using the J 35616-A Connector Test Adapter Kit will prevent damage to the harness connector terminals.
Use the J 35616 connector test adapter kit for any test that requires probing the ECM harness connector or a component harness connector.
Check for the following conditions:
| • | Poor connections at the ECM or at the component--Inspect the harness connectors for any backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. Refer to Wiring Repairs in Wiring Systems, or Engine Control Module Diagnosis , Checking Terminal Contact for the proper procedure. |
| • | Electromagnetic interference may have caused this DTC to set. |
| • | A misrouted harness--Ensure that the harness is not routed too close to any high voltage wires such as spark plug leads, or too close to any high current devices such as the alternator, motors, solenoids, etc. |
| • | A damaged harness--Inspect the wiring harness for any damage. |
Refer to Symptoms for the Intermittents.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | |
2 |
Was an electromagnetic interference condition found and corrected? | -- | Go to Step 4 | Go to Step 3 |
3 | Replace the camshaft position sensor. Refer to Camshaft Position Sensor Replacement . Is the action complete? | -- | Go to Step 4 | -- |
4 |
Does the scan tool indicate that the diagnostic Passed? | -- | Go to Step 5 | Go to Step 2 |
5 | Does the scan tool display any additional undiagnosed DTCs? | -- | Go to the applicable DTC table | System OK |
