Thread‑secured onto side of manual transmission housing, this mechanical‑driven speed sensor utilises internal plastic drive gear to capture rotation movement from gearbox output shaft. It converts mechanical rotary motion into continuous electrical pulse signal. Dashboard instrument cluster relies on this signal to show real‑time driving speed and accumulate odometer mileage; meanwhile diesel engine ECU uses speed information to refine fuel‑injection logic and gear‑shift auxiliary judgement.
Long‑term van delivery workload, gear‑box oil soaking and under‑chassis thermal fluctuation will degrade internal sensing element and drive gear. Repair technicians will encounter typical driving symptoms: speedometer pointer stays at zero while engine cranks normally, pointer fluctuates violently during highway travel, odometer fails to accumulate mileage, and occasional power‑cut phenomenon under heavy‑load driving. Many workshops spend considerable time inspecting dashboard wiring harness before tracing fault back to this compact transmission‑installed sensor.
This aftermarket replacement sensor replicates factory‑spec mounting hole dimension, driven‑gear tooth count and three‑pin plug definition for NV350 Urvan E26 ZD30DDTi diesel van. Built‑in small rubber O‑ring prevents gear‑box lubricant seepage from threaded mounting opening. Mechanics can complete sensor swap with simple hand tools without full gearbox disassembly.
