2002 Buick Park Avenue, Regal SMU Revised DTC P0341 Camshaft Position (CMP) Sensor Performance

This bulletin is being issued to revise DTC P0341 Camshaft Position (CMP) Sensor Performance in the Engine Controls-3.8L sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information. This revised DTC requires a different diagnostic approach due to a change that affects diagnosis of the camshaft position (CMP) sensor circuit. The change affects the CMP circuit by possibly causing an "engine cranks but does not run" condition if the powertrain control module (PCM) does not recognize the CMP sensor signal. The PCM may or may not set DTC P0341 depending on if the engine was running at the time of the failure.
The following information has been updated within SI2000. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.
Circuit Description
The camshaft position (CMP) sensor is a hall-effect type sensor. The sensor produces one signal for each revolution of the camshaft in order to control the sequential fuel injection. There are no direct circuits from the CMP sensor to the powertrain control module (PCM). All of the circuits are between the CMP sensor and the ignition control module (ICM). These circuits are the CMP signal circuit, the 12-volt reference circuit, and the low reference circuit. The ICM also supplies a camshaft position signal circuit to the PCM. The PCM compares the CMP sensor signal to the number of 3X, low-resolution, engine speed signals generated by the ICM. The normal ratio of 3X signals is 6 to 1. If the PCM receives an incorrect number of CMP sensor signals, this DTC sets.

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