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Q: No start and buzzing noise - 2006 BMW 525xi

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I was having trouble with my car starting this morning. I got in, put the key in the groove, pressed the button and it wouldn’t start. I just heard a buzzing noise. My brake pedal was firm, the steering wheel wasn’t locked and the radio, lights and the air conditioner were all turned on. My battery is less than a year old, too. Do you know what could be wrong?

The battery still needs to be checked to ensure there is a charge level sufficient for starting the vehicle. There could be a possible issue with the CAS module. This computer is part of the starting immobilizer system. It verifies a valid key remote and then in concert with the engine computer and transmission computer will initiate the engine starting sequence. Again low battery voltage can cause this process to malfunction. The battery needs to be charged and load tested to ensure it is not faulty. If the battery checks out good, then the CAS system will need to be interrogated by a scan tool capable of reading its information and if it needs to be replaced then it will need to be purchased from a dealer and programmed in order to be operational. You may need to consult a BMW dealer or specialty shop to determine the source of starting system failure.

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