XC70 L5-2.5L Turbo VIN 59 B5254T2 (2003)
generates a current which oscillates between 7 mA and 14 mA, and whose frequency increases with speed. Using the signal from the sensor, the
transmission control module (TCM) calculates the transmission speed, unit rpm.
The transmission control module (TCM) uses information about the input shaft speed to calculate the torque reduction to be requested from the engine
control module (ECM) when shifting. The value is also used to compare the engine speed (RPM) with the speed of the input shaft in order to calculate
the slipping rate of the torque converter. The value is also compared with the transmission speed sensor signal in order to calculate the actual gear
ratio. This is done to check whether the value corresponds to the expected gear ratio.
There are diagnostics for the transmission input speed sensor.
Transmission output speed sensor (speed of the output shaft)
The transmission output speed sensor (speed of the output shaft) is on the reverse of the transmission housing. The sensor provides signals to the
transmission control module (TCM) about the vehicle speed. The output shaft speed sensor is an active sensor and is supplied with 12 V. When the
pulse wheel (wheel for shift-lock) rotates the sensor generates a pulsed current (quadratic wave) where the strength of the current depends on the
position of the pulse wheel. The signals from the coils in the sensor are then affected by a magnetic resistance element, which generates a current
which oscillates between 7 mA and 14 mA, and whose frequency increases with speed. The control module calculates the transmission output speed
using the signals from the sensor. The signal is compared with the signal from the transmission input speed sensor and is used to calculate the gear
ratio and is also used for diagnostics. There are diagnostics for the transmission output speed sensor.
Oil temperature sensor
The temperature sensor is an NTC sensor. The temperature sensor is on the transmission control system inside the side cover. It gauges the
temperature of the transmission fluid in the oil pan. The temperature sensor is integrated in the cable harness. The temperature sensor is supplied with
5 V and is grounded via the transmission control module (TCM). The control module can determine the transmission fluid temperature by measuring
the voltage drop above the NTC resistance of the sensor. The control module stores the time the temperature has been within a certain temperature
range. If a certain temperature and time has been exceeded, a diagnostic trouble code (DTC) indicating that a oil change is necessary is stored.
There are diagnostics for the temperature sensor.
Gear-shift position sensor
