Toyota Corolla

1992-1998 of release

Repair and car operation

Toyota Corolla
+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engines
+ 4. Systems of cooling, heating
+ 5. Fuel, exhaust systems
+ 6. System of decrease in toxicity
- 7. Transmissions
   + 7.1. Mechanical transmission
   - 7.2. Automatic transmission
      7.2.1. Specifications
      7.2.2. Diagnostics
      7.2.3. Replacement of epiploons
      7.2.4. Butterfly valve rope
      7.2.5. A being switched rope
      7.2.6. The switch blocking inclusion of a starter by included transfer
      7.2.7. Transmission fastening
      7.2.8. Removal and transmission installation
+ 8. Coupling and semi-axes
+ 9. Brake system
+ 10. Suspension bracket and steering
+ 11. Body
+ 12. Electric equipment

7.2.2. Diagnostics



Malfunction of an automatic transmission can be caused by five general reasons: bad operation of the engine, the wrong adjustment, malfunction in hydraulic system, mechanical malfunction or malfunction of the computer or its alarm system.

Diagnostics of these problems always is necessary for beginning check of the next moments which are easily giving in to correction: check level and quality of liquid of an automatic transmission (see subsection 2.7.5), check adjustment of the connecting mechanism of a transmission and a butterfly valve. Further, pass on the car and check, whether malfunction was eliminated or it is necessary to continue diagnostics.

If after carrying out preliminary checks and adjustments malfunction was not eliminated, further diagnostics of a transmission is necessary for entrusting experts. Cм. subsection 1.5.36 for obtaining information on the reasons of malfunctions of a transmission.

Preliminary checks

1. Pass on the car to warm up a transmission to normal working temperature.
2. Check level of liquid of an automatic transmission.
3. If level of liquid is lowered, add liquids to demanded level, and then check a transmission on tightness (see below).
4. If level of liquid is raised, merge surplus, and then check the merged liquid on existence in it cooling liquid. Availability of cooling liquid of the engine in liquid of an automatic transmission testifies that the walls of an internal radiator dividing cooling liquid and transmission liquid, lost tightness (see subsection 2.3).
5. If transmission liquid foams, completely merge it from a transmission and fill in new, then check old liquid on presence at it cooling liquid of the engine, and also check, whether level of transmission liquid in a transmission raises.
6. Check speed of operation of the engine in an idling mode.


If the engine is faulty, do not carry out preliminary checks while it will not be repaired and will begin to work normally.

7. Check adjustment of a rope of a butterfly valve. Adjust it if it is necessary (see subsection 7.2.4).


Adjustment of a rope of a butterfly valve can be correct when the engine is switched off also cold, but can not correspond demanded at operation of the hot engine. Check rope adjustment in both cases, when the engine cold and when it is heated-up to normal working temperature.

8. Examine switching ropes of a transmission. Check, that they were correctly adjusted and went freely (see subsection 7.2.5).

Tightness check

The majority of leakages of transmission liquid is easy for finding visually. Repair usually consists in epiploon or laying replacement. If leak is heavy for finding, arrive as follows.

1. Define, what liquid proceeds. Be convinced that it is transmission liquid, instead of oil of the engine or brake liquid (liquid of an automatic transmission has red color).
2. Try to establish a leak place. Pass on the car some kilometers, then establish it over a big sheet of paper or a cardboard. In one-two minutes you can find a place of leakage of the liquid dripping on a cardboard.
3. Carefully examine places, from where there can be a leak, and area round them. Pay special attention to connections in which laying is used. For survey of trudnodostizhimy places, use a mirror.
4. If you nevertheless do not manage to find a leak place, carefully clear area where probably there is a leak, by means of an obezzhirivatel or solvent, and then wipe it dry.
5. Pass on the car some kilometers on various speeds at normal working temperature of a transmission. Then, again examine area where, probably, there is a leak.
6. After leak detection, it is necessary to define its reason. If you replace laying, but edges of connection will be погнуты, new laying will not eliminate leak. The Pognuty edge is necessary for leveling.
7. Before leak elimination, check, that the following possible reasons of emergence of leak were eliminated, as they can lead to formation of leak again.


Of such reasons it is possible to eliminate some only by means of the special equipment and existence of the corresponding experience. At detection of such malfunctions, address to experts.

Leaks through laying

Periodically check the oil pallet. Check, that bolts were reliably tightened, there were no absent bolts, laying was in a good condition, and the pallet was not will bend (dents on the pallet can testify to existence of damages to the block of valves inside).

If laying of the pallet proceeds, means, level of liquid or its pressure can be too high, the final opening can be closed, bolts of fastening of the pallet are tightened too hardly, edges of the pallet погнуты, edges of a case of a transmission are damaged, laying or a case of a transmission is damaged can be will burst or to have a porous wall. If instead of laying between a case of a transmission and the pallet hermetic was used, it is possible that incorrect hermetic was applied.

Leak through epiploons

If transmission any of epiploons proceeds, means, level of liquid or its pressure can be too high, the final opening can be closed, the nest of installation of an epiploon can be damaged, the epiploon can be damaged or incorrectly established, the surface of the shaft passing through an epiploon, can be damaged or the worn-out and loosened bearing can cause excessive, free movement of a shaft.

Check, that the tube epiploon щупа for measurement of level of transmission liquid was correctly established. Periodically check area round a drive of a speedometer or the sensor of speed on existence of traces of leak. If they are present, check a sealing ring on existence of damages.

Leaks through a case

If the case proceeds, means, case walls porist, and it is necessary to repair or replace it.

Check, that connections of hoses of cooling liquid were reliably tightened and in a good condition.

Liquid follows through a tube of a final opening or a tube of filling of liquid

It means that liquid level in a transmission is too high, cooling liquid mixes up with transmission liquid, case walls porist, is incorrectly inserted щуп, the final opening or drain channels is closed.