Linear Pressure Solenoid, SLC1, SLC2, SLC3 and SLB1

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2009 Volvo S60, 2008 Volvo S60, 2007 Volvo S60, 2006 Volvo S60, and 2005 Volvo S60. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Linear Pressure Solenoids In Transmission Control System

Courtesy of VOLVO CARS OF NORTH AMERICA.

The linear pressure solenoids SLC1, SLC2, SLC3 and SLB1 and are located in the transmission control system, which is fitted on the front edge of the transmission. The designation of the solenoid is linked to the component (clutch/brake band) that the solenoid controls. The linear pressure solenoids consist of an electrical coil that controls a hydraulic valve. The solenoids are controlled with a pulse width modulated (PWM) voltage and are grounded via the transmission control module (TCM). The solenoids have a linear hydraulic function. The hydraulic valves are controlled by the varying current resulting from the current pulse ratio. With a high pulse ratio, i.e. high current strength (approx. 1 A), the system pressure is low. With a low pulse ratio, i.e. low current strength, the system pressure is high. In the event of an open circuit the system pressure is at a maximum, resulting in hard shifting. Here, the hydraulic valve is fully open.

The solenoids can be diagnosed.