P0340

CIRCUIT DESCRIPTION
The Camshaft Position (CMP) sensor correlates the crankshaft to camshaft position so that the Powertrain Control Module (PCM) can determine which cylinder is ready to be fueled by the injector. The CMP sensor also determines which cylinder is misfiring when a misfire is present. If the PCM receives an intermittent signal from the CMP, then the CMP Resync Counter will increment. When the PCM cannot use the information from the CMP sensor, a DTC is set and the PCM will fuel the engine by using the Alternating Synchronous Double Fire (ASDF) method.

CONDITIONS FOR RUNNING THE DTC
The engine is running.

CONDITIONS FOR SETTING THE DTC
The CMP Active Counter is not incrementing.

ACTION TAKEN WHEN THE DTC SETS
^ The control module illuminates 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 MIL/DTC
^ The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
^ A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
^ 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
^ Whenever the PCM sees less than 15 resyncs in 256 seconds, the counter resets to 0. Any time a poor connection is present, the cam sensor active counter stops incrementing and the cam sensor resync counter starts to increment.
^ Inspect the wiring harness for damage. If the harness appears to be OK, observe the CMP resync counter on the scan tool while moving connectors and wiring harnesses related to the CMP sensor. If the CMP resync counter still does not count, while observing the scan tool, operate any non-engine related electrical components on the vehicle. A change in display will indicate the location of the malfunction.
^ A defective reluctor wheel or a cracked or damaged CMP sensor can result in an intermittent. Remove the camshaft sensor and inspect for any damage. With the CMP sensor removed, you can also inspect the reluctor wheel through the hole. Check the porosity and condition of the wheel. The edges must be square, look for a nicked or damaged wheel.

If this DTC is determined to be intermittent, refer to intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Steps 1-11:

Steps 12-17:

The numbers below refer to the step numbers on the diagnostic table.
8. This step determines if there is a problem with the signal circuit.
9. If the fuse is open in the jumper wire, there is a short to ground on the signal circuit.