Due to the complexity of the AT design, it will be difficult for the average amateur mechanic to accurately diagnose its failures and perform repairs. In the event of problems other than those listed below, the car owner should seek help from specialists at a car service workshop. You should also not rush to dismantle a faulty transmission, since many of its checks are performed in situ (in its regular place).
| Symptom | Possible cause |
| ATF leaks | ATF is usually dark red in color. Its leaks should not be confused with those from engine oil - the latter can be carried to the transmission housing by the oncoming air flow. |
| To identify the source of the leak, first of all, clean the transmission housing and surrounding surfaces from dirt and grease - use a high-quality degreaser or steam clean the unit. Take the car for a short drive at low speed (so that traces of the leak are not carried far from its source). Jack up the car and place it on supports. Inspect the transmission case, visually identifying sources of ATF leakage. The most common sources are: | |
| a) Transmission oil pan (see Chapters Routine car maintenance and Automatic transmission (AT)); | |
| b) ATF filler neck tube (see chapter Automatic transmission (AT); | |
| c) Transmission connection pipes with ATF cooler and their fittings (see chapter Automatic transmission (AT)); | |
| d) Speedometer sensor (see chapter Automatic transmission (AT)). | |
| ATF turns brown or smells burnt | The ATF is burnt and needs to be replaced. Internal transmission defects are possible (see Chapters Routine car maintenance and Automatic transmission (AT)). |
| The transmission does not automatically downshift (kick-Down mode) when the gas pedal is fully depressed | The adjustment of the Kick-Down mode drive cable is disturbed (see chapter Automatic transmission (AT)). |
| There are general problems with gear selection | In Chapter Automatic transmission (AT) describes the procedures for checking and adjusting the AT gearshift rod. The most common problems that may be associated with a rod adjustment problem are listed below: |
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| The transmission "jumps" from the selected position, shifts with difficulty or noise, or does not provide forward or backward movement of the car | There are many possible causes for the listed failures, but only one of them falls within the competence of the average amateur mechanic - a violation of the ATF level. Check, if necessary, top up/replace the fluid (see chapter Routine car maintenance). In all other cases, the car should be taken to a car service workshop for diagnostics and transmission repair/replacement |
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