Power Steering Control Module
| ITEM | DESCRIPTION |
|---|---|
| 1 | Electric motor power supply connector |
| 2 | Torque sensor connector |
| 3 | Diaphragm |
| 4 | PSCM cover |
| 5 | PSCM system connector |
The power steering control module is located on the end of the electric motor, under a hermetically sealed cover. A diaphragm in the cover, made from a waterproof breathable fabric, maintains the interior of the cover at ambient pressure, avoiding the need for an open vent.
As well as the control circuitry, the power steering control module also contains the power electronics for operating the electric motor.
Power assistance is provided when the following are present:
- An ignition feed from the ignition relay in the Engine Junction Box (EJB).
- The power mode Controller Area Network (CAN) signal is set to engine running.
Electrical power for operation of the electric motor is provided by a permanent feed from the Auxiliary Junction Box (AJB). For 100% nominal power assistance, supply voltage must be between 10.5 and 18 V. If supply voltage is outside of these limits, power assistance is either reduced or discontinued.
The power steering control module receives hardwired digital inputs from the torque sensor and high speed CAN bus inputs of:
- Steering angle, from the steering angle sensor.
- Engine speed, from the Powertrain Control Module (PCM).
- Vehicle speed, from the Anti-lock Brake System (ABS) control module.
- Automatic steering requests, from the parking aid module (if park assist system fitted).
- Terrain mode request from the Terrain Response™ switch pack.
- Power mode from the Passenger Junction Box (PJB).
- Auto stop/start system stop request from the PJB (if Auto stop/start system fitted).
- Lane Keep Assist (LKA) and Lane Departure Warning (LDW) from Forward Facing Camera (FFC).
The power steering control module uses the input data and software algorithms to control electric motor operation. If required, the power steering control module can also transmit outputs, on the high speed CAN chassis systems, of:
- Warning status, to the instrument cluster.
- Steering status, to the parking aid module (if park assist system fitted) and Terrain Response™ switch pack.
- Auto stop/start system inhibit requests to the PCM (if Auto stop/start system fitted).
- Tie rod load forces.