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
+ 8. Fuel system
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
- 14. Electric equipment
   14.1.2. Measuring devices
   14.1.3. Technology of measurements
   14.1.4. Checks of electric equipment
   14.1.5. Sound signal
   14.1.6. Replacements of safety locks
   - 14.1.7. Rechargeable battery Unattended rechargeable batteries Check of the rechargeable battery Self-discharge of the rechargeable battery Charging of the rechargeable battery Storage of the rechargeable battery Diagnostics of malfunctions of the rechargeable battery
   + 14.1.8. Generator
   + 14.1.9. Starter
   14.1.10. Traction relay
   + 14.1.11. System of lighting
   14.1.12. Devices
   14.1.13. Dashboard
   14.1.14. Glow lamps on the dashboard
   14.1.15. Light switch
   14.1.16. Radio receiver
   + 14.1.17. Antenna
   14.1.18. Loudspeakers
   + 14.1.19. Rubber brushes of screen wipers
   14.1.20. Windscreen washer jets
   14.1.21. The washing nozzles of headlights
   14.1.22. Screen wiper and its engine
   14.1.23. Protect the car
   14.1.24. Anticreeping "immunodeficiency"
   14.1.25. Why headlights grow dull
   14.1.26. Galogenka
+ 14.2. Electrical circuitries Self-discharge of the rechargeable battery


Depending on equipment of the car the natural category of the rechargeable battery is promoted by consumption of current various control systems even in that case when the engine does not work. Therefore at the standing car it is necessary to recharge the rechargeable battery every four weeks. If suspicion of leak currents on the surfaces of insulators is available, check electric onboard network.

Use the charged rechargeable battery to check.

1. Disconnect a weight(s) wire from the battery plug.

At the same time all saved-up data in electronic memory devices as, for example, an anticreeping code of radio are erased. Before shutdown of the rechargeable battery it is also necessary to read the recommendations provided in subsection 14.1.7.

2. Establish on the ampermeter (measurement range from 0–5 мА to 5 A) the maximum limits of measurement. Turn on the ampermeter between the negative pole of the battery and a wire connecting its pole to the car case.


An inspection can be carried out as well by means of a control bulb. But if the bulb does not light up at its inclusion between a flexible crossing point and a negative pole of the rechargeable battery, then anyway it is necessary to use the ampermeter.

3. Disconnect all consumers of current, disconnect the electronic clock (the constant consumer of current) from plugs, close doors.
4. Switching ampermeter ranges, determine current size.
5. Removing safety locks, consistently disconnect various electric chains. If in one of the broken-off chains zero, is displayed here and it is necessary to look for a malfunction source. The correlated or polluted contacts through wiped wires, internal short circuit in units can be defects.
6. If in the electric chains protected by fuses defects are not found, then it is necessary to pull together tips of wires from the units which are not protected by fuses. Those are: system of ignition, generator and starter.
7. If at a detachment from plugs of one of the units unprotected by fuses indication comes back to zero, then repair or replace the corresponding detail. At detection of leakage of current in a starter or in system of ignition, first of all check the ignition switch according to the schematic diagram of electric equipment.
8. Connect a weight(s) wire to the accumulator plug.
9. Determine time, and also enter an anticreeping code for radio.