BMW 3 series E30

Since 1983-1994 of release

Repair and car operation

8.2.3. Diagnostics of automatic transmission

THE GENERAL DATA

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The prevention

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

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Preliminary checks

Make a trip to warm up transmission.

Check up level and a liquid condition (subsection 2.6 see). If level considerably below norm restore liquid level in transmission and check up presence of leaks outside (Check of a condition of transmission on liquid leak see).

If liquid level in transmission above norm check up presence of pollution by a cooling liquid of the engine which could get to a cooler because of infringement of its tightness (a cooler is mounted in a radiator). If трансмиссионная a liquid foamy merge it and check up presence in it of impurity of a cooling liquid.

Check up a liquid condition on probeе on colour and a smell. Dark colour and "a burnt" smell specifies in malfunction of transmission or on infringement of terms of change of a liquid.

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

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

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The prevention

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

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

Check of a condition of transmission on liquid leak

The liquid leak is easily established on dark red colour and eliminated by replacement of epiploons or linings. If a leak weak. That carefully clear картер and check up places of consolidations after a trip. For detection of an appreciable leak park the car after a trip on some km over a cardboard or paper blank leaf. After nearby 2 mines the leak can be found out. If a leak very weak she can be established on потекам, absolutely having wiped картер.

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

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

Before leak elimination establish character and the reasons of a leak and define a kind and volume of repair work as independently it is impossible to execute set of kinds of repair. The Most typical kinds of a leak are considered more low.

Flow from under pallet linings there can be a consequence of increase of pressure or level of a liquid owing to a contamination of ventilating apertures, deformations of the pallet or its demountable plane, discrepancy of the applied mark of hermetic recommended, defects of moulding of the pallet, easing of bolts of fastening, pallet deformation that can cause breakage of the block of valves of transmission.

Flow from under an epiploon can to be caused increases of pressure or level of a liquid owing to a contamination of ventilating apertures, wrong installation of an epiploon, damage of a condensed neck of a shaft or deterioration of the bearing of a shaft.

The leak картера is caused by defects of moulding. Check reliability of fastening of hoses of a cooler of a liquid.

The leak from сапуна or from a refuelling branch pipe specifies in transmission overflow, hit of a cooling liquid, wrong position of the index, a contamination of ventilating and drainage channels.