A multi-charge ignition system including a spark plug control unit adapted to control at least two coil stages so as to successively energise and de-energise the coil stages to provide a current to a spark plug, the two stages including a first transformer including a first primary winding inductively coupled to a first secondary winding a second transformer including a second primary winding inductively coupled to a second secondary winding. A first switch is located between the high end side of the first primary winding and the high end side of the second primary winding, and a second switch is located between the low side of the first primary winding and high side of the second primary winding.

Various embodiments of the present technology comprise a method and apparatus for a current circuit. According to various embodiments, the current circuit may be utilized for current detection or current limiting. The current circuit may be configured to compensate for a base current, making detection of an input current more accurate.

Various embodiments of the present technology comprise a method and apparatus for a current circuit. According to various embodiments, the current circuit may be utilized for current detection or current limiting. The current circuit may be configured to compensate for a base current, making detection of an input current more accurate.

An ignition control apparatus according to one embodiment of the present invention is an ignition control apparatus which generates, in an ignition coil, a voltage to be supplied to a spark plug that is provided in an internal combustion engine on the basis of a pulse signal induced in the ignition coil of the internal combustion engine, wherein the ignition control apparatus comprises at least a switch element for passing current through and discharge the ignition coil, and a controlling unit that acquires the timing for discharge the ignition coil in response to a first pulse of the pulse signal, and controls the switch element so that a current flows through the ignition coil in response to a second pulse that follows the first pulse and the ignition coil is opened on the basis of the discharge timing acquired in response to the first pulse.

An ignition control apparatus according to one embodiment of the present invention is an ignition control apparatus which generates, in an ignition coil, a voltage to be supplied to a spark plug that is provided in an internal combustion engine on the basis of a pulse signal induced in the ignition coil of the internal combustion engine, wherein the ignition control apparatus comprises at least a switch element for passing current through and discharge the ignition coil, and a controlling unit that acquires the timing for discharge the ignition coil in response to a first pulse of the pulse signal, and controls the switch element so that a current flows through the ignition coil in response to a second pulse that follows the first pulse and the ignition coil is opened on the basis of the discharge timing acquired in response to the first pulse.

A method of determining a sliding camshaft actuator pin position based on engine crankshaft angle includes commanding a sliding camshaft actuator to perform a valve step shift, and monitoring an actuator's pin position during the valve step shift command. At least one crank angle is measured when the actuator pin position reaches or exceeds at least one predetermined pin position threshold and at least one remedial action is performed when the actuator pin position does not correlate to the at least one measured crank angle.

A method of determining a sliding camshaft actuator pin position based on engine crankshaft angle includes commanding a sliding camshaft actuator to perform a valve step shift, and monitoring an actuator's pin position during the valve step shift command. At least one crank angle is measured when the actuator pin position reaches or exceeds at least one predetermined pin position threshold and at least one remedial action is performed when the actuator pin position does not correlate to the at least one measured crank angle.

A vehicle power supply box device includes: a first system which feeds electric power to first group electric parts requiring constant feed of power supply electric power; a second system which feeds electric power from to second group electric parts requiring feed of power supply electric power in response to a state of an ignition switch. The device further includes: a recovery switch portion connected between a second input side power supply line and an input of the first system; an input abnormality detecting portion which detects presence/absence of abnormality in the input of the first system; and a recovery control portion which controls the recovery switch portion to be turned ON/OFF in accordance with the presence/absence of the abnormality detected by the input abnormality detecting portion.

A vehicle power supply box device includes: a first system which feeds electric power to first group electric parts requiring constant feed of power supply electric power; a second system which feeds electric power from to second group electric parts requiring feed of power supply electric power in response to a state of an ignition switch. The device further includes: a recovery switch portion connected between a second input side power supply line and an input of the first system; an input abnormality detecting portion which detects presence/absence of abnormality in the input of the first system; and a recovery control portion which controls the recovery switch portion to be turned ON/OFF in accordance with the presence/absence of the abnormality detected by the input abnormality detecting portion.

Methods and systems are provided for diagnosing a knock sensor of an engine system by actively inducing knock in an engine cylinder. A laser ignition device is operated in an engine cylinder located closest to the knock sensor while the engine is at rest and with the cylinder parked with an intake valve and an exhaust valve closed to generate and trap heat in the cylinder. Spark timing is advanced in the cylinder on the subsequent restart, which in combination with the trapped heat induces knock, and elicits a response from a functional knock sensor.