Oil temperature sensor

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2007 Volvo V70, 2006 Volvo V70, 2005 Volvo V70, 2004 Volvo V70, and 2003 Volvo V70. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Oil Temperature Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

The temperature sensor is the NTC type. The temperature sensor is located on the transmission control system inside the side cover and measures the temperature of the transmission oil in the sump. The temperature sensor is an integrated part of the cable harness. The temperature sensor is supplied with 5V and is grounded via the Transmission Control Module (TCM). By measuring the voltage drop over the sensor's NTC resistor the control module can determine the temperature of the transmission oil. The Transmission Control Module (TCM) uses the information on transmission oil temperature for:

calculating transmission gearshift timing
calculating engagement and disengagement of the lock-up function.

The Transmission Control Module (TCM) stores the time for which the temperature has been within a certain temperature range and if a certain temperature and time has been exceeded, then a diagnostic trouble codes (DTC) is generated to indicated that an oil change is necessary.

The temperature sensor can be diagnosed.