Q: 2006 BMW 750LI no start code po335 I need pin point test and diagram please .thank you

To test the crankshaft position sensor (Sensor Circuit "A" in your case, if the code is P0335) the fault memory of the DME control unit is read and then the test schedules contained in the BMW diagnostic tool are followed. If you are trying to get a preliminary idea regarding possible failure of the sensor, you can attempt a few tests using a volt ohmmeter. Your car has a three wire sensor so there should be: 1) a constant voltage to the sensor (typically battery voltage or a 5 volt reference from the computer); 2) a good ground to the sensor; and 3) a varying sensor output. The output will be AC and if you get any output at all, by just simply cranking the engine, typically the sensor is good. Output may appear on your volt meter as more or less constant voltage though as most simple voltmeters will not refresh quickly enough to display actually varying real time voltage. If you have a reference voltage, a verified ground, and sensor output, what you might want to do is request a diagnostic to further pinpoint the issue. As you may know, there are multiple causes of a P0335 fault codes. If you suspect an issue with the sensor and/or want to schedule a diagnostic, the recommended service is a check engine light diagnostic. If you request that service, the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.