There are a few possible causes of low voltage to the camshaft sensor. One possibility is that the sensor itself is faulty and needs to be replaced. Another possibility is that the engine is not getting enough power from the battery. This could be due to a problem with the battery itself, or with the alternator. Additionally, if there is something wrong with the wiring between the battery and the sensor. This could be due to a loose connection, or a break in the wire.