FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

System Overview






System overview

Electro hydraulic power steering




The power steering system employs the electro-hydraulic principle and is controlled by the Power Steering Control Module (PSCM). The control module regulates the power steering assistance based on input signals. This allows it to provide optimal steering assistance, irrespective of whether the vehicle is stationary with the engine running or is being driven at high speed. The functions managed by the Power Steering Control Module (PSCM) are active when the engine is running.
The control module is under the right-hand headlamp. The control module and pump motor make up a single replaceable unit.
The Power Steering Control Module (PSCM) is powered by the battery (30 supply) via a fuse in the integrated relay/fuse box in the engine compartment. The Power Steering Control Module (PSCM) receives a 15 supply via the ignition switch and is unfused in the integrated relay/fuse box in the engine compartment and in the central electronic module (CEM). The Power Steering Control Module (PSCM) is grounded to the front side member via a ground lead.
The Power Steering Control Module (PSCM) communicates with other control modules using controller area network (CAN) communication.

Signals
The table below summarizes the input signals to and output signals from the Power Steering Control Module (PSCM). The signal types are divided into directly connected signals and CAN communication. The illustration below displays the same information with the Volvo component designations.