Suzuki Jimny

Part-time 4WD positions a transfer case between the driveshafts running from the front and rear differentials, and uses it to switch between 2WD and 4WD as required. When in 4WD, the system directly connects the front and rear wheels, making it possible to distribute engine power to all four tyres evenly and without loss.

The feedback control used on normal full-time 4WD vehicles allocates torque to the rear wheels after detecting front wheel slippage. As well as feedback control, it also offers feed-forward control that anticipates slippage based on road surface, throttle opening position, steering angle and other factors, and allocates the torque to the rear wheels before any slippage can occur. Rather than reacting after grip is lost, controlling the vehicle to prevent grip being lost in the first place results in greater stability.

Synergetic Vehicle Dynamics Control is a function to stabilise the drive by monitoring the drive conditions through a steering angle sensor, yaw rate sensor, and other systems, and synergetically controlling the 4WD control and power steering control. The Synergetic Vehicle Dynamics Control properly allocates steering assist torque and front and rear wheel torque, suppresses any vehicle side skid tendency at the stage before ESP control intervenes, and assists drive stability.

For example, when an oversteer tendency occurs with the rear wheels are about to slide or spin on the outer side, the Synergetic Vehicle Dynamics Control assists with a counter steer through the power steering and simultaneously allocates torque to assist the front wheels. Conversely, when an understeer tendency arises with the front wheels losing grip and the vehicle curving to the outer side, the Synergetic Vehicle Dynamics Control allocates the drive power to favour the rear wheels and stabilises the drive.

Also, in the case of a push-understeer tendency, which occurs when the rear wheel drive power is too pronounced in relation to the front wheels turning force, the VDSC allocates the torque to assist the front wheels. The Synergetic Vehicle Dynamics Control is essentially a system to assist stable driving and is not intended to raise the limits on drive and turning performance.

ESP® is also optimally controlled for each mode. In SPORT mode, ESP® weakens traction control intervention to maximise the driver's sense of controlling the vehicle. In SNOW mode, ESP® allows traction control to intervene strongly to maximise stability. In LOCK mode, ESP® enhances extrication performance by using a traction control system to apply braking to wheels that are spinning without traction and prioritises torque allocation to tyres that are gripping. At the same time, it curbs the amount of the engine's torque reduction control to provide the torque needed to escape.

ESP is a registered trademark of Daimler AG. The degree of engine torque reduction, the wheels that brake and their braking force vary according to the driving conditions. ESP® is essentially a system to assist stable driving. In the case of slippage or skidding that exceeds the limits of grip between tires and road surface, ESP® will still function but may not be effective.

To amplify driving pleasure, the power train too is controlled in SPORT mode. It modifies throttle‑torque performance in the low and medium engine speed range to give a livelier drive experience. And in the case of CVT vehicles it also helps maintain the engine speed at higher levels, improves acceleration, and offers sports driving performance.