Circuit/System Description
WARNING: This page is about a different car, the 2017 Chevrolet Spark. However, it is still accessible from the selected car via links, so may be relevant.
For an overview of the component/system, refer to Horns System Description and Operation
| Circuit | Description |
|---|---|
| B+ - Relay Coil | Supplied from a fuse. |
| B+ - Relay Switch | Supplied from a fuse. |
| Signal - S33 Horn Switch | The control module input circuit has an internal resistance connected to 12 V. |
| Control - P12 Horn | The output circuit is switched to 12 V to activate the component. |
| Control - Relay Coil | The output circuit is switched to ground to activate the component. |
| Ground - S33 Horn Switch | Chassis Ground |
| Ground - P12 Horn | Chassis Ground |
| Component | Description |
|---|---|
| P12 Horn | The horn has an electromagnet which pulls a diaphragm inwards and simultaneously opens a contact which interrupts the current through the magnet. When the diaphragm springs back, the contact is closed and the cycle starts over. The vibration of the diaphragm produces the sound. |
| S33 Horn Switch | The switch has a normally open contact. When the switch is activated, the signal circuit to the control module is grounded. |
| K9 Body Control Module | The module controls various vehicle functions like lighting, central door locking, power windows, etc. |
| X50A Fuse Block - Underhood | The fuse block houses various fuses and relays. |