What is the function of the O/D button?

1 Answers
Zoey
07/29/25 7:31pm
O/D button is a forced downshift button, its function is to force a vehicle running in 4th gear to downshift to 3rd gear, thereby obtaining greater power and engine braking force. When this switch is turned on, the overdrive gear (O/D gear, i.e. 4th gear) is automatically used in D position. When this switch is turned off, the O/D-off light on the dashboard illuminates, and the D position can only reach up to 3rd gear at this time. More information about the O/D button is as follows: 1. The O/D button is mostly used when encountering situations such as overtaking, uphill, or downhill driving. 2. When cruising at high speed on the highway, the O/D gear can be selected to save fuel. For 4AT models, when the vehicle speed reaches 80km/h, the transmission has basically shifted to 4th gear, which means it is in an overdrive state. When rapid overtaking is needed, press the "O/D button" to downshift to 3rd gear, the engine speed increases, torque increases, and stepping on the accelerator can quickly overtake. 3. When driving downhill for a long time, to avoid overheating of the braking system due to prolonged braking and reduced braking effectiveness, the O/D button can be used to downshift from 4th gear to 3rd gear, utilizing engine braking force to decelerate. 4. When driving at low speed in congested urban areas, press the "O/D button" to activate "O/D-OFF". The transmission gear is limited to within 3rd gear, reducing unnecessary switching of internal shift solenoids, while the vehicle being in a lower gear also facilitates acceleration.
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