DSA (Dynamic Stability Assistance) is a dynamic stability control system that specially developed for compact Volvo models. This prevents the drive wheels from slipping and improves traction on wet and slippery surfaces. This system contributes to rapid acceleration and helps maintain the desired direction when manoeuvring.
How the DSA works
The RPM of a of each wheel is monitored with the help of the ABS sensors. So if one of the front wheels turns faster than the rear wheels, this system sends a message to the FENIX engine control unit. It turns off one or more injectors, reducing engine torque until traction is restored. The extent to which this happens depends on the speed of the crankshaft, the throttle valve position and also the pressure in the intake manifold. The system does not trigger the braking mechanisms – that's the difference to a traction control system.
Popular Volvo models with DSA
- S40 VS, 644
- V40 VW, 645
Causes of defects
- Defective wheel speed sensors
- Oxygen sensor connections
- Engine faults
- Control unit failure.
