The so-called "automatic" automatic transmission (A/T) is not limitless, it is an automatic transmission in a certain range and conditions, and this range and conditions are determined by operator through gear lever and appropriate switch or key for installation. There are many automatic transmission switches and buttons such as overdrive button, mode select button, hold switch, gear lock switch and kickdown switch. How to work with these buttons in order to achieve effect of safety and fuel economy?
1. HOLD switch
Some automatic transmissions (such as R4A-EL type manufactured by Japanese company JATCO) are equipped with a lock switch, function of which is to block automatic gear shifting of automatic transmission.
The holding switch is usually mounted on shift lever, and some are mounted on shift console. Buick Excelle and Chevrolet Jingcheng use 4HP-16 automatic transmissions and their lockout switches are located on left side of shift lever and on shift console. The two ends of holding switch are labeled "A" and "M", where "A" indicates automatic switching and "M" indicates manual switching. Press switch "A" end, "HOLD" indicator will go out, and it is in automatic switching mode; Press end of "M" switch, keep switch on, and "HOLD" indicator will light up. on instrument panel is lit, The transmission temporarily loses automatic shift function, and gear shifting can only be done manually by driver through gear lever, as is case with a manual transmission. In HOLD mode, if shift lever is in D, S (or 2) or L (or "1"), automatic transmission will remain in 3rd, 2nd or 1st gear respectively, which is advantageous to suppress slippage of drive wheels.
If vehicle is starting or driving on an icy, snowy, or muddy road, you can press lockout switch and transmission will engage in 2nd gear (instead of 1st), which reduces output torque and helps reduce tire slip on change earth.
When parking and starting off on a steep uphill road, if you do not have skills, car may reverse. At this time, if you switch to HOLD start, you can prevent vehicle from moving backwards.
Note: The 4HP-16 automatic transmission malfunction indicator is aligned with "HOLD" indicator. If indicator is constantly on, it means that transmission is in manual mode, program.
2. Gear lock switch
Most automatic transmissions are equipped with a shift lock system, and a shift lock solenoid valve is installed at bottom of shift lever controlled by A/TECU. If brake pedal is not pressed to change gear, system locks shift lever in P or N so that shift lever cannot move, preventing driver from accidentally shifting gears; brake pedal is depressed, AVTECU releases lock mechanism, which locks shift lever through shift lock relay, lock is released and shift lever can be shifted to other gears. Some automatic transmissions (such as A342E type) have a shift lever lock override button next to shift lever. Driver error (for example, direct gear shifting without depressing brake pedal) resulted in a sharp jerk of car and damage to automatic transmission.
3. Manual switching
For a manual/automatic transmission, Manual mode allows driver to manually select appropriate gear between 1st and 4th gear, as in a manual transmission, without having to change gears, as in a manual transmission. When shifting gears, depress clutch pedal.
In manual shift mechanism of an automatic transmission, shift lever and manual valve are connected by a connecting rod or cable and have an adjustment position. The position of manual shift knob must alternately correspond to position of spring card in automatic transmission, if not, then it must be adjusted. Sometimes after repairing automatic transmission, due to fact that gearshift mechanism is not adjusted, impact force of gearshift is too large, and even an accident occurs.
After entering manual shift mode, gear position indicator should show "1", if it does not show "1", this means that automatic transmission indication system is faulty.
For a CVT automatic transmission, place shift lever in D and then move shift lever to right to put automatic transmission into manual mode; move shift lever left or right to engage automatic transmission. transmission in sport mode.
The DCT (Dual Clutch) automatic transmission is equipped with a manual shift switch. In position D, you can also use manual channel to move shift lever slightly up and down to allow upshifting. or sequentially down.