Rear Left ABS/Wheel Speed Sensor - 1991 300ZX Z32

The Nissan 300ZX Z32 platform employs a discrete hall-effect wheel speed sensor at the rear left knuckle, designated by Nissan as 47901-40P00 (later superseded to 47901-40P01). This active sensor detects a magnetic tone ring pressed onto the rear hub assembly, transmitting a digital square wave signal to the ABS controller. When sourcing from junkyards, interchange covers all 1990-1996 USDM model years indiscriminately, fitting both VG30DETT twin-turbo and VG30DE naturally aspirated variants, but strictly distinguish from the right-side counterpart 47900-40P00 due to asymmetric pigtail routing. Diagnostic failures typically manifest as open circuits (infinite resistance) or intermittent signal dropouts caused by oxidized connector terminals. Verify integrity by measuring 1.2–1.6 kΩ across the sensor pins or inducing 0.5V AC while rotating the hub. During installation, meticulously clean the tone ring of metallic sludge and corrosion to prevent erratic readings, and apply dielectric grease to the weatherpack connector to mitigate the moisture intrusion endemic to these three-decade-old components.