Central Electronic Module (CEM): Function: Horn

Fig 1: Identifying Horn

Courtesy of VOLVO CARS CORPORATION

The horn (16/10-11) is located behind the radiator grille. The horn is supplied power from the horn relay (2/17) in the engine compartment fuse and relay box. The horn is activated when a switch in the steering wheel is closed. The closure is detected by the steering wheel module (SWM) (3/130), which sends a signal to the central electronic module (CEM) (4/56). The central electronic module (CEM) forwards a ground closure on one of its outputs, grounding the signal horn relay and activating the relay.

The horn is grounded in the body.