BMW 7_aya the E38 series from 1994 to 2002
1. Introduction
2. Governing bodies and methods of operation
3. Settings and routine maintenance of the car
3.1. General information
3.2. General information about settings and adjustments
3.3. Schedule of routine maintenance
3.4. Check of levels of liquids, control of leaks
3.5. Check of a state and replacement of hoses and tubes in a motive compartment, localization of leaks
3.6. Replacement of motive oil and oil filter
3.7. Clearing and replacement of the fuel filter
3.8. Check of the brake system and coupling
3.9. Check of a condition of system of production of the fulfilled gases
3.10. Check of a condition of components of a suspension bracket and steering
3.11. Check of a condition of protective covers of CV JOINTS of power shafts
3.12. Replacement of the AT gearbox oil
3.13. Replacement of brake fluid and pumping of the brake system
3.14. Replacement of spark plugs
3.15. Replacement of the saloon filter (system of ventilation)
3.16. Replacement of the filtering air cleaner element
3.17. Replacement of cooling liquid
3.18. Check of a condition of tires and pressure of their rating
3.19. Check of a condition of the battery and care of it
3.20. Check of a condition of a belt of the drive of auxiliary units
3.21. Check of a condition of brushes of screen wipers and adjustment of nozzles of washers
3.22. Replacement of oil of the main transfer
3.23. Check of thickness of the conducted clutch plate
4. Engine
5. Cooling systems of the engine, heating, ventilation and air conditioning
6. A power supply system and production of the fulfilled gases
7. Systems of electric equipment of the engine
8. Manual box of gear shifting and coupling
9. Automatic transmission
10. Cardan and power shafts, reducer, differential and stupichny assemblies
11. Brake system
12. Suspension bracket and steering
13. Body
14. Onboard electric equipment
15. Schemes of electric equipment


3.19. Check of a condition of the battery and care of it

Address also materials of the Head Sistema of electric equipment of the engine. The rechargeable battery is placed at the left in a forward part of a motive compartment (see illustrations Components of a motive compartment of models with the M52 engine, Components of a motive compartment of models with the M51 engine, Components of a motive compartment of models with the M62 engine).

During the work with the battery it is necessary to take certain security measures. At banks of the battery there is always extremely a flammable hydrogen therefore do not allow an arrangement about the battery of naked flame. Electrolyte of the battery represents solution of sulfuric acid which at hit in eyes or on open parts of the body causes serious injuries. Besides, acid corrodes clothes and paints. At shutdown of the battery always the first disconnect a negative wire, and connect it in the last turn!


  1. Care of the battery is the important procedure which implementation requires the corresponding tool.
  2. Before the procedure of service always at first switch off the engine and switch-off all electric devices, and then disconnect a negative wire from the battery.
  3. The considered cars can be completed with various batteries: served or unattended, and also with or without indicator of a charge and level of electrolyte. On unattended batteries only check of level of electrolyte is supposed, and adjustment of its level is not provided.
  4. Check electrolyte level in each of battery cans – it has to be between the marks "MIN" and "MAX" in the battery case. If tags are not visible, on the served battery turn out a stopper and glance inside – the level of electrolyte has to reach a plastic edge. If on the battery there is an indicator, the level of electrolyte and a charge can be checked on its color. For example, green color of the indicator indicates a normal charge, the black indicator testifies to the low level of a charge, and decoloured or pale yellow color the indicator indicates the low level of electrolyte.
  5. If the served battery is used, if necessary bring electrolyte level to the required value separately for each section, having added the distilled water through the openings closed by traffic jams.

Overflow of cans can lead to transfusion of electrolyte during the accelerated charging that will cause corrosion and damage of the components, next to the battery.

  1. If the positive plug and a collar of a wire of the battery are equipped with a rubber protector, make sure that it is not torn and is not damaged. It has to close the plug completely.
  2. It is necessary to examine periodically an external condition of the battery on existence of such damages as cracks in the case.
  3. Check reliability of tightening of nuts of collars of wires of the battery providing good electric connection. Check each of wires on all length for existence of cracks and attritions of isolation and the carrying-out core.
  4. At detection of traces of the corrosion (which is usually representing a friable raid of white color) disconnect wires from plugs, smooth out them a wire brush and again connect. Emergence of corrosion can be minimized by installation of specially processed washers, or having processed contacts by acid-free vaseline or suitable lubricant.
  5. Make sure that the bolt of a fixing collar is reliably tightened. If the battery was removed from the pallet, track that in installation time on it any foreign objects did not lie. Do not tighten its bolt of a fixing collar too hardly – see Specifications.
  6. Additional information on the battery and on start of the engine from the auxiliary power supply can be found respectively in the Head Sistemy of electric equipment of the engine and in Introduction.

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3.18. Check of a condition of tires and pressure of their rating
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3.20. Check of a condition of a belt of the drive of auxiliary units