E30 series BMW 3

since 1983-1994 of release

Repair and car operation

+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engine
+ 4. Cooling system
+ 5. Heating and ventilation
+ 6. Fuel system
+ 7. Exhaust system
- 8. Transmissions
   + 8.1.2. Specifications
   - 8.2. Automatic transmission
      8.2.2. Specifications
      8.2.3. Diagnostics of automatic transmission
      8.2.4. Draft of the selector of transmission
      8.2.5. Kick-down-mode cable
      8.2.6. The blocking switch / switch of a signal of a backing
      8.2.7. Removal and transmission installation
      8.2.8. Epiploons of automatic transmission
      8.2.9. "Machine gun"
+ 9. Coupling
+ 10. Brake system
+ 11. Running gear
+ 12. Body
+ 13. Electric equipment
+ 14. Good advice


8.2.3. Diagnostics of automatic transmission



Malfunction of the engine (capacity loss), the wrong adjustments, refusals of hydraulic system of transmission, mechanical drive and processor control system can be the main reasons for abnormal work of transmission. First of all it is necessary to check level and a liquid condition, to adjust draft of a drive and a zaslonka. If these measures do not lead to positive result, it is necessary to address in car-care center.

Preliminary checks

Make a trip to warm up transmission.

Check level and a liquid condition (see subsection 2.6). If level is much lower than norm, restore liquid level in transmission and check existence of leaks outside (see. Check of a condition of transmission on leakage of liquid).

If liquid level in transmission is higher than norm, check existence of pollution by cooling liquid of the engine which could get to a cooler because of violation of its tightness (a cooler it is mounted in a radiator). If transmission liquid foamy, merge it and check availability of impurity in it cooling liquid.

Check a liquid condition on щупе on color and a smell. Dark color and a "burned" smell indicates malfunction of transmission or on violation of terms of change of liquid.

Check turns of idling of the engine. If necessary execute repair and adjust, as further checking of transmission is not meaningful.

Believe freedom of moving of a cable of a kick-down-mode.

Malfunction of a cable of a kick-down-mode can be shown only on the heated-up engine. Therefore check cable work at first on cold, and then on the heated-up engine.

Check adjustment and smoothness of moving of a drive of transmission.

Check of a condition of transmission on leakage of liquid

The leak of liquid is easily established on dark red color and eliminated with replacement of epiploons or laying. If leak weak. that carefully clear a case and check places of consolidations after a trip. For detection of an appreciable leak park the car after a trip on some km over a blank sheet of a cardboard or paper. Later about 2 mines to flow it is possible to find. If very weak, it it is possible to establish a leak on потекам, having absolutely wiped a case.

The leak communicates an air stream that complicates its detection. Therefore execute checks at various speeds of movement, and also when parking car.

If the place of a leak is established, define the reason of a leak and a way of repair (for example, it is impossible to eliminate with replacement of laying a leak if the demountable planes are deformed).

Before elimination of a leak establish character and the reasons of a leak and define a look and volume of repair work as a set of types of repair independently to execute it is impossible. The most characteristic types of a leak are considered below.

The leak from under laying of the pallet can be a consequence of increase of pressure or liquid level owing to a contamination of ventilating openings, deformation of the pallet or its demountable plane, discrepancy of applied brand of hermetic recommended, defects of molding of the pallet, weakening of bolts of fastening, pallet deformation that can cause breakage of the block of valves of transmission.

The leak from under an epiploon can be caused increases of pressure or liquid level owing to a contamination of ventilating openings, the wrong installation of an epiploon, injury of a condensed neck of a shaft or wear of the bearing of a shaft.

The leak of a case is caused by defects of molding. Check reliability of fastening of hoses of a cooler of liquid.

The leak from сапуна or from a refueling branch pipe indicates transmission overflow, hit of cooling liquid, the wrong provision of the index, a contamination of ventilating and drainage channels.