Body Electronics - Overview: Overview MINI Cooper I

Principle of Operation

The Power Distribution system reacts to the vehicle demand for electrical power. Current from the battery is routed through the fuses and harnesses to the component demanding power. The battery smooths out voltage fluctuations allowing components to receive a fixed voltage level.

The generator reacts to power demands and battery voltage supplies operating current during times of high demand. The high capacity of the generator ensures that sufficient power is always available.

Circuit protection is afforded by the fuse system. Excess amperage demands either through defective component or wiring harness fault are quickly reduced to protect the vehicle.

The battery location of the MINI COOPER S requires additional protection due to its long B+ battery cable. It is protected by a 250 amp fuse and the BST located in the battery compartment.

Notes

Vehicle Identification Number (VIN)

The VIN is stored at the end of production or when the BC1 is replaced. The VIN can only be written to the BC1 if the total mileage is less than 100 km or there is no VIN already stored.

The starting sequence of the EWSIII 3.3 is as follows

1. The key is inserted into the lock cylinder and switched "ON". The EWS III (3.3) control module is powered through KL R and sends a 125kHz AM signal to the ring antenna. The AM signal induces voltage in the key coil and powers up the transponder.
2. Powered up, the key transponder sends the key identification code to the EWSIII 3.3 module. The EWSIII 3.3 module verifies the key identification code and checks to see if the key is enabled. If the key is correct and enabled, a password is sent to the transponder over the 125kHz AM signal through the ring antenna.
3. When the transponder accepts the password, it releases the changing code which it received from the EWSIII 3.3 module during the last start-up operation to the EWSIII 3.3 module via the ring antenna.
4. The EWSIII 3.3 module compares the changing code received from the transponder with the code stored in its memory and if they match the process is allowed to continue. The EWSIII 3.3 module looks at the other inputs for correct status (e.g. Code function not active, Transmission in P or N or clutch depressed, engine speed below specified RPM) and energizes the internal relay to begin starter operation.
5. While energizing the internal starter relay, the EWSIII 3.3 module calculates a stored code from the "Rolling Code Table" and sends the calculated results to the EMS 2000.
6. On receipt of the "Rolling Code" from the EWSIII 3.3 the EMS calculates it's own stored code and compares its results with the code it received from the EWSIII 3.3. If the "Codes" match the drive away protection is released and injection and ignition are enabled and the engine starts. If the "Codes" do NOT match, the EMS "rolls forward" to the next code according to the "Rolling Code Table" and makes the same calculations. The EMS continues this "forward roll" up to a maximum of 200 times or until a match is found. Failure to find a match will result in the engine cranking but not starting.
7. When the ignition is switched off and no engine RPM is present in both the EMS and the control module each module will automatically "roll forward" to the next predetermined code based on the "Rolling Code Table". This new code is used for the next starting sequence.

Conventional Operation

Pressing and holding the sunroof switch in the open/close position will cause the sunroof to operate in either direction and operation will continue until the switch is released or the sunroof has reached its travel limit.

One-Touch Operation

Pressing and quickly releasing the switch in the open/close direction will cause the sunroof to either open/close to its travel limit, except in the close direction where the sunroof will stop in the tilt position and manual operation of the switch is required to complete closing.

Primary to the driver receiving accurate tire defect information is the initialization of the system. Without proper and current initialization the system may issue false warnings or may fail to issue a warning when necessary.

With the ignition ON the microprocessor of the control module performs a self-test and checks the peripheral components for correct functioning. If the microprocessor does not recognize any faults, the system is operational after approximately one second.

After a successful self-test the PDC control unit is ready to function, and will be switched on when reverse gear is selected for longer than one second. The system is automatically deactivated when the transmission is taken out of reverse gear.

The microprocessor specifies the chronological time frame of the clearance measurements

1. PDC control unit transmits a "send" command via the signal lines to the sensors in accordance with a fixed specification.
2. The sensors then send an ultrasonic oscillation packet.
3. The echo, which has been reflected from an obstruction, strikes the sensor after a time period that is proportional to the clearance.
4. The echo signals are amplified in the sensors and changed into digital signals. These signals are then sent back to the microprocessor in the PDC unit via the signal line.
5. The echo transmission times are determined and the clearances of the individual sensors to the obstruction are calculated from this.

The quartz frequency of the microprocessor serves as the time basis for the measurement of the echo transmission time. The clearance between the converter and the obstruction is calculated from the transit time between the beginning of the transmission and the output of a low signal (echo reception). The position of the obstruction and the minimum clearance between the vehicle and the obstruction are derived from the calculated clearances of the individual converters and from the measured clearances by the 2 respective adjacent converters.

An acoustical warning is provided via the acoustical transmitter if the vehicle is in reverse gear and it approaches an obstruction to within 0.6 m for the outer sensors and 1.5 m for the center sensors. The clearance message consists of audio pulses with a duration of 75 ms. The pause between the audio pulses becomes shorter in proportion to the distance as it diminishes. Below the minimum clearance of 0.25 m, the audio sequence converts to a continuous tone. If the clearance to the obstruction remains constant, the center converter maintains the last actuated audio repetition frequency. For the outer converters, the clearance warning is switched off after 3 seconds in this event in order to indicate that the vehicle is moving next to a wall and not approaching an obstruction.