- poor quality adjustment;
- faults in the hydraulic system;
- faults in the mechanical system;
- malfunctions in the computer or its electrical circuit.
First of all, check the level and condition of the oil in the gearbox and the adjustment of the rods.
Preliminary control
Take the vehicle for a test drive to warm up the transmission.
Check the gearbox oil level.
Check the engine idle speed.
Check the accelerator cable for freedom of movement and adjust if necessary.
Check the operation of the gear selection mechanism.
Make sure there are no leaks at the gasket and sealing ring locations in the gearbox.
Warnings: A burnt oil smell is a sign of oil contamination with small particles due to wear of the friction linings of the automatic transmission control elements. This should be a warning sign, as a major transmission overhaul may be required.
If the oil level in the automatic transmission is below normal, air will begin to enter the oil pump, which will lead to the formation of an oil-air mixture. This in turn will cause a decrease in the operating pressure in the control system, slippage of the friction control elements of the transmission and extended gear shifts.
If the oil level is higher than normal, then as a result of the rotation of the planetary gears, the oil will begin to foam heavily, which will lead to the same consequences as in the case of a low oil level.
The formation of an air/oil mixture will eventually cause the oil to overheat and oxidize, which will adversely affect the operation of the valves and friction controls. In addition, foaming will cause increased oil discharge through the breather, which may be mistaken for oil leaks from the system.