45 Information on PSM

WM 4500IN Information on PSM

Information on PSM

PSM is an active control system to stabilise the vehicle at the limit of driving dynamics. Sensors continuously determine:
- Vehicle speed
- Direction of travel (steering angle)
- Lateral acceleration
- Longitudinal acceleration
- Rotation rate

Information

- The PSM (Porsche Stability Management) is automatically ready/switched on after each engine start.

Off-road PSM

When the Low Range/Off-road programme is switched on, an off-road PSM specially adapted for off-road terrain to improve traction is automatically activated. At speeds below 35 km/h, the off-road PSM reacts later in the case of under or oversteering and improves the steering control.

Switching off PSM

Press the PSM switch. The PSM switches off after a short delay.

When the PSM is off, the PSM OFF warning light in the instrument panel and the indicator light in the switch are lit.
- When braking, the vehicle is also stabilised when the PSM is switched off.
- One-sided wheel spin is also prevented when the PSM is switched off.
- On Tiptronic vehicles, the slip upshift function is switched off when PSM is switched off -> 45 Information on PSM - section on "Information". Characteristic features of Tiptronic vehicles (slip upshift).

The PSM should always be switched on for normal driving.

In the following exceptional cases, it can be advantageous to switch off the PSM temporarily:
- On a loose surface and in deep snow
- When rocking the vehicle free
- When using snow chains
- On extremely difficult terrain (if one or more wheels have little or no road grip - engine performance is reduced)

Switching PSM back on

Press the PSM switch. The PSM switches on after a short delay.

Characteristic features of Tiptronic vehicles (slip upshift)

- When a maximum permissible speed difference between front and rear axle is exceeded, the integrated slip monitoring shifts into the next highest gear. This increases the driving stability on slippery roads.
- When PSM is switched off, the slip monitoring (slip upshift function) is also switched off. In this way, the Tiptronic enables an active sporty driving style even when the friction coefficient is low as is the case with manual transmission vehicles.