LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volvo >> 2014 >> XC70 T6 >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Ignition And Control Systems - Design And Function >> Engine Control Module (ECM) >> Engine Control Module (ECM) [2014-2016, B4204T11] >> Design >> Supercharger Clutch
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Supercharger Clutch

GLL1014129Courtesy of VOLVO CARS CORPORATION
  1. Gear wheel to gear unit.
  2. Return springs (3 x)
  3. Flange.
  4. Friction plate.
  5. Connector.
  6. Coil.

The task of the supercharger clutch is to connect respectively disconnect the compressor from driving the crankshaft.

The clutch is a magnetic clutch. In a powerless state, the compressor is disconnected by means of three return springs.

During the mechanical engagement of the compressor, as smooth an engagement as possible is ensured by control modules lowering the ignition, while the clutch engagement is controlled to a controlled slippage for about half a second. The control signal, which is an adapted PWM signal (12V), initially gives a strong signal to quickly move the magnetic clutch to the engaged position. Thereafter the signal's strength is reduced to allow the clutch to slip easily during the engagement.

Precisely how the PWM signal appears depends on relevant factors such as engine speed, temperatures and ageing.

For information about electrical connection, see wiring diagram. For sensor characteristics and normal values, see signal specification and component specification.

The supercharger clutch can be diagnosed by the Engine Control Module (ECM) and signals for requested position on the clutch can be read out.