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Home >> Volvo >> 2004 >> XC70 >> Repair and Diagnosis (Single Page) >> External Pages >> Different car >> Section 9 (Alarm System, Control Modules, Engine Management Systems - Design And Function) >> Central Electronic Module (CEM) (2001-2004) >> Design >> Horn
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Central Electronic Module (CEM) (2001-2004): Design: Horn

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2007 Volvo V70, 2006 Volvo V70, 2005 Volvo V70, 2004 Volvo V70, and 2003 Volvo V70. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Horn
GLL106028Courtesy of VOLVO CARS OF NORTH AMERICA.

There are two horns in front of the radiator. There are four switches in the steering wheel. The horn is activated when one of these is closed.

The signal continues for as long as the switch is closed.

The horn is also activated when the panic alarm button on the remote control is pressed (certain markets).

The power supply to the horns is via a relay in the relay box in the engine compartment.

There are diagnostics for the relay for the horn.