Most modern cars warn the driver when there is a problem with the automatic transmission or when the transmission fluid needs to be checked by turning on the check transmission light in red or yellow, however, some other cars use other methods to warn about this. The most frequently asked questions in phone calls or in-person visits to us are related to the symptoms that drivers suddenly receive. In this section, we have tried to explain these warning signs in various cars with automatic transmissions.
All modern cars (1995 and up) are controlled by computers. The automatic transmission computer performs two tasks:
1 - Starting the transmission and receiving information from the engine, transmission, ABS, and through this information, it performs commands to perform transmission operations such as adjusting oil pressure and changing gears.
2- Simultaneously with number 1, a second task is also performed, which is troubleshooting. If the computer detects any faults that have been defined, it is instructed to enter emergency gear. This situation is to prevent further damage and keep the car on the road, and the driver will realize that there is a problem with the transmission and should go to the repair shop as soon as possible.
Peugeot 206 and 207 cars and all French cars with AL4 gearboxes will have the S* light flashing 3 times, accompanied by a beep and a knock, and the gearbox will enter 3rd gear and remain in this position.
Mercedes-Benz: Engine check light on and no gear shifting or knocking in all gears.
BMW: Yellow or red gear light on and no gear shifting or knocking in all gears.
Mazda 3: AT light on.
Mazda 323: Hold light flashing and no gear shifting and staying in 3rd gear.
Nissan Maxima: The AT light, which is specific to the automatic transmission, normally turns on for 2 seconds after the switch is turned on and then turns off, but if there is a fault or problem in the transmission, this light flashes 10 times and then turns off.
Nissan Murano: The CVT light turns on when there is a fault or problem in the transmission.
Hyundai and Kia: In these types of cars, the Check Engine light turns on and remains on if a fault or problem occurs.