Nubira SE Sedan L4-2.0L DOHC D-TEC MFI (2001)
Transmission Speed Sensor: Description and Operation
AUTOMATIC TRANSMISSION INPUT (SHAFT) SPEED SENSOR (A/T ISS)
The A/T ISS is a magnetic inductive pickup that relays information relative to transaxle input speed to the PCM. The PCM uses transaxle input speed
information to control line pressure, TCC apply and release and transaxle shift patterns. This information is also used to calculate the appropriate
operating gear ratios and TCC slippage.
The input speed sensor mounts on the transaxle case under the channel plate and next to the drive sprocket.
An air gap of 0.010 - 0.114 inch (0.26 - 2.90 mm) is maintained between the sensor and the teeth on the drive sprocket. The sensor consists of a
permanent magnet surrounded by a coil of wire. As the drive sprocket is driven by the turbine shaft, an AC signal is induced in the input speed sensor.
Higher vehicle speeds induce a higher frequency and voltage measurement at the sensor.
Sensor resistance should measure between 625 - 725 ohms at 68° F (20° C). Output voltage will vary with vehicle speed from a minimum of 0.5
volts AC at 550 RPM to 200 volts at 7000 RPM.
