Ma Chi (MARCH) is Nissan Motor Co. recently put on the market a mini family car, the car is equipped with a 1.5 L engine, matching 4-speed automatic transmission and 5 speed manual transmission, in order to facilitate the readers understanding of the car, this technique introduces some of its highlights.
First, the automatic transmission
Ma Chi is RE4F03C car equipped with 4-speed electronically controlled type automatic transmission (FIG. 1), which the transmission section of the transmission for older a number of improvements.
FIG 1
1. Mechanical System
(1) Mechanical structure and size
compared to the old transmission, the transmission of new structure and improving the characteristics of the transmission mechanism of the automatic shifting components , so that the transmission size reduction, weight loss of 15% (FIG. 2).
FIG. 2
(2) a torque converter
using the variable hydraulic car is smaller than the torque converter TIIDA used (FIG. 3), in the case to ensure smooth engine operation, the transmission quality can be reduced to improve the fuel economy of the vehicle.
Figure 3
2. Automatic transmission control system
(1) CAN communication control
Which transmission employs integrated control of the engine and an automatic transmission, in order to improve the shift feel. When the sudden starting and sudden acceleration, the engine output control signal transmitted between each ECM and TCM (FIG. 4), coordinated control in real time according to driving conditions.
Figure 4
(2) The shift control
In the case where the throttle opening degree , to change from the first speed gear or gear 2 to the third speed change time from 2 (Sudden acceleration or sudden acceleration), TCM sends a request to reduce a torque output signal to ECM. The torque reduction request signal, the ECM delayed ignition timing of the engine output torque is temporarily decreased while the vehicle speed sensor is used to track the TCM in the transmission case, the shift control to achieve optimum shift timing.
(3) self-diagnostic function
If the automatic transmission control system failure, can be read by a diagnostic trouble code or OD-OFF lamp. If there is no fault control system, when the ignition switch is opened, OD-OFF lamp will light 2 s, and the solenoid valve inspection performed.
through the self-diagnosis starting signal input, the fault code is output, OD-OFF lamp on the instrument cluster flashes to indicate the fault location. If a fault exists, the fault indicator region corresponding to the lighting time (FIG. 5). When the ignition switch is turned off after the completion of self-diagnosis, indicating failure region to be cleared.
Figure 5
Second, the vehicle electrical system
1. Central locking system
car central locking system controlled by the BCM, the doors can be the driver’s door key cylinder by the operation of the driver-side door lock switch knob with a central locking / unlocking . Key in the ignition key cylinder and the driver’s door is opened, the side door when the operation knob switch or central door latch of the driver, the rear door lock to be opened immediately in order to prevent the car keys are locked in the car. When the driver’s side door lock knob, when the handle is pulled, it is only the driver’s door open, the door can be opened.
(1) central door lock control system diagram
central locking control system diagram shown in Fig.
Figure 6
(2) the main system elements
①BCM
BCM central door lock switch according to the driver’s side door and a detection switch (integrated in the driver’s side door lock actuators) signal, to control all door lock actuator.
Central locking switch ②
When the door lock / unlock, signals the BCM.
③ door lock actuator
is mounted in the door lock actuator locks the doors, the locking by the BCM / unlock signal locking or unlocking the doors.
④ key insertion detecting switch
key insertion detection switch detects the insertion of the key, and sends a signal to the BCM.
2. Remote Keyless Entry System (non-smart key control system)
remote control transmitter (integrated with the key together) transmitting a radio wave, the remote receiver receives the signal, and sends a signal to the BCM. Check BCM remote ID, it will match only when the locking / unlocking the doors.
When the remote control locking / unlocking the vehicle door as an operation check, hazard warning lights flashing. When the door is unlocked by remote control, the interior lamp room lamp control function is turned on by a timer, when the latch door, interior lights off. Remote control door lock system diagram shown in Fig.
Figure 7
In the case where the remote control is lost, can register a new remote control, you can register up to 5 times. You can use the remote control key manual registration ID, you can also use the diagnostic registration, inspection and removal of ID.
3. Smart key system
capable of a smart key system without a key, locking the driver / unlock the doors and start the engine, the operation is performed through bidirectional communication between a smart key and the vehicle.
Figure 8
When the smart key unit detects a request switch which isWhen pressed, it activates the corresponding external and internal antenna switch is pressed door request. Activated antenna request signal to the smart key, the smart key and checks whether the vicinity outside the vehicle and whether the vehicle door in. When the smart key located outside the detection area of the antenna (FIG. 8), receives the smart key ID request signal and transmits the key to the smart key unit. Smart key unit receives the key ID with the ID signal and the signal is checked against registered in the car. If the key ID check results are positive, the smart key unit or unlocking the door lock request signal to the BCM via CAN communication bus. When BCM receives the door lock or unlock signal, which starter door lock actuator, while the hazard warning lights flash to check work.
When a failure of the smart key system, key fob near ldquo; start button rdquo; the lower end of the window (FIG. 9), while pressing ldquo; rdquo ;, the start button to activate the ignition key NATS backup system, the vehicle engine can be started properly work.
Figure 9
4. NATS security system
All models are used MARCH Nissan NATS as dedicated immobilizer antitheft control devices, safety indicator is mounted (FIG. 10) is controlled by a combination meter in the BCM. Each of the mechanical key is assigned an ID code, only those registered ID in the BCM and the ECM key to start the engine.
10
intelligent key to start the engine under the control of the BCM. If the customer needs, you can register up to five keys (including the standard key group). When registering key ID repairs, replacement of parts or adding a mechanical key, the previously used mechanical key already registered must register again. Therefore, we must first of all get the key from the user.
5. Power window system
(1) power window control system diagram
power window control system diagram shown in Figure 11.
11
(2) pinch function
If the driver’s side when the power window rises when the clip to the obstacle, the window will drop 150 mm. When the driver’s door by the obstacle corresponding to the clamped or shock loads, and in accordance with environmental conditions, the window may be decreased.
12
side power window motor driving system has a conventional limit switch and a pulse sensor. In the power window motor vehicle drive system, the limit switch has been removed, the two pulse sensors installed (FIG. 12) to simplify the structure. To the control system, and the position information of the glass required direction of movement of glass. Therefore, if the inspection or maintenance system is missing location information or location information fails, you must initialize the system.
13
power window switch the number of pulses emitted by the pulse sensor 1 is calculated for each revolution of the motor shaft to detect when the glass motion. Then, it detects the difference pulse signal having a pulse sensor to determine the direction of movement of the glass (FIG. 13). Read pulse power window main switch and sensor signals to determine the status of the door glass 12 and performs a control operation. By automatically controlling the power window rises or when the ignition switch is in a location other than ON (when the timer is turned on), if an obstacle is pinched and fixed load or a greater driving force the side members of the door glass, the pulse signal of the sensor 1 signal changes. Reading the change in the power window switch signal so that the upward movement of the power window motor is stopped, the down signal transmission the driver side door glass drop fixed amount.
FIG 14 is a waveform signal to start the anti-trapping
(3) fail-safe function
rising when the driver’s door glass, the decoder if the signal detecting direction of motion is detected appear irregular, or if the difference between the actual position and the fully closed position of the power window switch glass stored in glass when a fault is detected, the process proceeds to fail-safe control operation of the system is in initialization state. After
(4) The method of setting
the driver’s side of the anti-trapping power window
The following operation is completed, the driver-side power window initialized: [123 .]
① initialization procedure:
a ignition switch ldquo; ONrdquo; position;
b or the door glass half opened. more;
c upward movement of the power window switch operation, when the glass stops at the fully-closed position, hold the switch 3 s or more;.
d. If opening and closing operation is continuously performed more than 10 times, it may cause failure of pinch function.
Note: the previously executed initialization procedure must disconnect the battery or power window switch connector terminal.
② to cancel the anti-trapping program
Method 1: The ignition switch ldquo; ONrdquo; position, the door glass half or more open, disconnect the electric window motor operatively plug and the power window switch 1 s or more.
Method 2: disconnecting the battery harness period.
(Wang)