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Automatic transmission faults

Automatic transmission faults Dipstick Oil Level Most faults in an automatic gearbox are caused by the oil level being too low. Torque Converter If the torque converter is damaged the car may not accelerate properly. Downshift cable Controls the gearbox kickdown facility. If the cable is damaged or badly adjusted, the gearbox will not change down when you need it. Selector linkage If the linkage is badly adjusted gear selection may suffer. Inhibitor switch Prevents the engine from being started in any gear other than 'neutral' or 'park'. If it is broken the engine may not start or there is a danger of the car being accidentally started in drive. Ventilation grille Helps to keep the torque converter cool. Make sure it is not blocked by dirt or debris, otherwise the gearbox may overheat.

Because of the large number of parts inside an automatic gearbox, some faults may be caused by more than one component.

The first check should always be on the transmission fluid level and its condition — if it is all right, then you will need to check the other points shown here.