Mercedes of the S-class W202

1993-2000 of release

Repair and operation of the car

Mercedes W202
+ 1.2. General information
+ 2. Maintenance
+ 3. Engines
+ 4. Lubrication system
+ 5. Cooling system
+ 6. Heating, ventilation
- 7. System of ignition
   7.2. Safety measures at repair of electronic system of ignition
   7.3. Ignition coils
   + 7.4. Spark plugs
   - 7.5. Device of a preliminary warming up of the diesel
      + 7.5.1. Check of the device of a preliminary warming up
      7.5.2. Self-diagnostics of the device
+ 8. Fuel system
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electrical circuitries

7.5. Device of a preliminary warming up of the diesel


The device of a preliminary warming up consists of the relay of management of a warming up of candles of an incandescence, 4/5-rod candles of an incandescence and a control bulb of a warming up on the dashboard. In the cold engine only the compression is not enough for fuel ignition therefore the engine has to be warmed.

Duration of a warming up depends on ambient temperature and copes by means of the relay of management of a warming up.

At malfunction of candles of an incandescence or the tokopodvodyashchy feeding wire of the relay of management of a warming up switch-off the incandescence device. Glow plugs are provided with electrotension by means of the parallel scheme.

If the ignition key remains in the provision of a warming up without launch of the engine, then the safety scheme of the relay of management of a warming up later switches-off 20-25 seconds the incandescence device. For renewal of a warming up the ignition key at first has to be installed in 0 situation.

At turning on of the device of an incandescence through each glow plug current about 30 proceeds And. Thanks to an adjusting winding consumption of current a candle at increase in temperature is limited to 8-15 A. Thereby the glow plug is protected from an overload.

The rod glow plug consists generally of the case with a vpressovanny heating core. The heating core in turn consists from included consistently heating and adjusting winding. When giving tension the heating winding strongly heats up. After 9 seconds of time of an incandescence temperature of a heating core makes 900 °C, and 30 seconds later the maximum temperature reaches 1180 °C.

For improvement of the characteristic of warming up of the engine idling, further warming up at the working engine depends on temperature of cooling liquid. Time of repeated warming up at the 2,0 l engine makes at most 17 seconds. At the 2,2 / 2,5 l engines repeated warming up reaches up to 3 minutes; at failure of the thermal sensor of cooling liquid connected with repeated warming up, duration of the last makes 30 seconds.

Maximum time of a prestarting warming up of the engine with a capacity of 2,2 / 2,5 l

– 30 °C
16 sec.
– 20 °C
12 sec.
– 10 °C
7 sec.
0 °C +30 °C
6–4 sec.