Which sensor may use two sets of slots to provide crankshaft position in degrees to the ignition module?

Which sensor may use two sets of slots to provide crankshaft position in degrees to the ignition module?

• A. Magnetic
• B. Hall-effect
• C. Optical
• D. Piezoelectric

Answer: (C)

Understanding crankshaft angle relies on decoding a multi-channel signal from a rotating wheel. An optical sensor can read two sets of slots on a tone wheel, producing two signals that are in quadrature (phase-shifted by a fixed amount). The ignition module uses this pair of signals to determine not only how far the crank has turned (in degrees) but also the direction of rotation, allowing precise timing for ignition. While magnetic or Hall-effect sensors can detect position with a magnetic target, they aren’t defined by two slot patterns, and piezoelectric sensors don’t provide this kind of rotational angle information. So, the two-slot optical setup is the standard way to deliver exact crank angle to the ignition module.

Understanding crankshaft angle relies on decoding a multi-channel signal from a rotating wheel. An optical sensor can read two sets of slots on a tone wheel, producing two signals that are in quadrature (phase-shifted by a fixed amount). The ignition module uses this pair of signals to determine not only how far the crank has turned (in degrees) but also the direction of rotation, allowing precise timing for ignition. While magnetic or Hall-effect sensors can detect position with a magnetic target, they aren’t defined by two slot patterns, and piezoelectric sensors don’t provide this kind of rotational angle information. So, the two-slot optical setup is the standard way to deliver exact crank angle to the ignition module.