Audi A4

since 1994 of release

Repair and car operation

A4 Audi
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ exhaust System
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and absorption channels
+ injection System
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tires
- Electrotechnical equipment
   The minus is connected to weight
   The help for orientation in the electrotechnical equipment of the car
   Connections of wires
   Central switching knot
   Support of additional relays
   Box for electronics
   Relay and control units
   Switching relay
   H-contact of the relay of unloading
   Table of the relay and control units
   Safety locks
   Table of safety locks
   + Electric circuits
   + Accumulator
   + Generator
   + Starter
+ ignition System
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ body Details
+ Salon
Search of malfunctions
Technical characteristics

H-contact of the relay of unloading

The unloading relay (the ordinary switching relay) plays a significant role in onboard the electrician. Therefore its function here is described:
On the plug 75 of the lock of ignition the current arrives only if the ignition key is in situation "Is included". Powerful consumers of a current, for example, the screen wipers, warmed back glass or the supercharger of air, are connected to this plug in order that at engine start on a starter there was all capacity of the accumulator. Certainly, not all these consumers can receive power supply through contact to the ignition lock; for this purpose it is too weak. Therefore between them the relay through which working contact current giving is carried out should be connected. Contact of the lock of ignition (along with current giving on headlights and the coil of the relay of a sound signal) provides only giving of a switching current to the relay.