Distance Systems, Cruise Control (Service Information) BMW M6 E63/E64

Scheme 1

Introduction

In 04/2000, Active Cruise Control (system supplier: BOSCH) was installed for the first time in a BMW as special equipment for the E38.

Active cruise control is an extension of the conventional cruise-control system (FGR). A comfortable distance and cruise control has been added to this. The distance from the vehicle ahead can be selected from 4 fixed timed separations. (EURO version: 1.0 - 1.5 - 2.0 - 2.5 seconds) Thus the spatial distance from the vehicle in front changes with the speed.

With Active Cruise Control activated, a speed in the range from 30 km/h to 180 km/h can be preselected.

The 2nd generation (ACC 2) Active Cruise Control option 541 will be introduced for the first time in 09/2004 on the E63/E64.

With the model year measures in March 2005, Active Cruise Control (ACC 2) will be introduced in more models: E60, E61, E65, E66.

1. E60, E61, E63, E64 before 09/2005, for more information, refer to «SYSTEM OVERVIEW FOR ACTIVE CRUISE CONTROL: E60, E61, E63, E64 UP TO 09/2005»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__system-overview-for-active-cruise-control) .
2. E60, E61, E63, E64 from 09/2005, for more information, refer to «SYSTEM OVERVIEW FOR ACTIVE CRUISE CONTROL: E60, E61, E63, E64 FROM 09/2005»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__system-overview-for-active-cruise-control) .
3. E65, E66 as from 03/2005, for more information, refer to «SYSTEM OVERVIEW FOR ACTIVE CRUISE CONTROL: E65, E66 FROM 03/2005»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__system-overview-for-active-cruise-control) .

Changes in ACC 2 compared to ACC 1 (in E38, E65 and E66 by 03/2005)

1. Radar sensor now has 4 radar antennae instead of just 3 This means the area covered by the radar sensor is widened from +/-4° to +/-8°.
2. The system is approximately 60 % smaller.

With the model year measures, the following changes to the Active Cruise Control option will be introduced in March 2005

> E60, E61, E63, E64 only

Additional scope of operation in combination of Car Communication Computer (CCC) with Professional navigation system option 609.

The dynamics of the Active Cruise Control change according to the characteristics of the roads. (The roads are split into road categories, e.g. motorways and highways. In addition, the general the number of bends on the route ahead is analyzed, i.e. if there are a lot of bends ahead, or just a few, as well as the radii of the bends.)

The advantages

In comparison with the previous ACC, ACC 2 offers the following advantages

1. more dynamic control behavior
2. The widened surveillance range of the radar sensor means that Active Cruise Control now works much better when cornering. Vehicles in front are monitored earlier Longer, more stable monitoring when following a vehicle (even in cases of tight bends)

System Overview For Active Cruise Control: E60, E61, E63, E64 Up To 09/2005

Inputs/outputs

Scheme 2

System circuit diagram

Scheme 3

System overview for active cruise control: E60, E61, E63, E64 from 09/2005

Inputs/outputs

Scheme 4

System circuit diagram

Scheme 5

System overview for active cruise control: E65, E66 from 03/2005

Inputs/outputs

Scheme 6

System circuit diagram

Scheme 7

Brief description of components

The Active Cruise Control option consists of the following components

1. ACC sensor with control unit The ACC sensor and control unit form a single unit. The ACC sensor monitors the distance, angle and relative speed of vehicles driving ahead. (Relative speed: The relative speed is the difference in speed between the two moving objects, i.e. relative to each other.) The ACC sensor is a radar sensor. The ACC sensor has a limited monitoring range (approximately 120 meters). For more information, refer to «ACC SENSOR WITH CONTROL UNIT: E60, E61, E63, E64, E65, E66»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__acc-sensor-with-control-unit-e60) .
2. Cruise control system steering-column stalk Cruise control is set and called up using the Active Cruise Control system steering-column stalk. For more information, refer to «STEERING COLUMN STALK FOR ACTIVE CRUISE CONTROL: E60, E61, E63, E64, E65, E66»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__steering-column-stalk-for-active-cruise) .
3. 2 brake pressure sensors A brake pressure sensor is installed in each of the front and rear axle brake circuits. The signals from the brake pressure sensors are evaluated by the Dynamic Stability Control. If Active Cruise Control is in use, the vehicle will be braked as necessary by the Dynamic Stability Control (DSC) (not DSC intervention). The brake pressure sensors regulate the brake pressure, which is often only very slight, on the front and rear axles. Vehicles with DSC 8Plus: The brake pressure sensors have been discontinued on vehicles with DSC 8Plus. DSC 8Plus is an advanced development of the familiar DSC 8. In addition, the ACC control unit communicates with the following control units
4. DME or DDE: Digital engine electronics or digital diesel electronics The DME/DDE controls the engine intervention. The following data is transmitted by the ACC sensor to the DME or DDE: Current torque request The following data is transmitted from the DME or DDE to the ACC sensor: Driver's command (signals from accelerator pedal module)
5. SGM: Safety and gateway module The SGM is the gateway (= data interface) between: > E65, E66 as well as E60, E61, E63, E64 up to 09/2005: PT-CAN K-CAN Byteflight The diagnostics cable is also connected at the SGM. > E60, E61, E63, E64 from 09/2005 The body-gateway module replaces the safety and gateway module (SGM). KGM: Body-gateway module > E60, E61, E63, E64 from 09/2005 The KGM is the gateway (= data interface) between: PT CAN K-CAN The diagnosis lead is also connected at the KGM.
6. DSC: Dynamic Stability Control The current status of the vehicle is detected by the DSC, for example by evaluating the following sensor signals: Yaw rate (measure of movement of the car about its vertical axis) Steering angle Information on the brake pressure Circumferential wheel speed DSC then transmits data about current operating conditions to the ACC sensor. The following data is transmitted by the ACC sensor to the DSC: Request for vehicle deceleration: DSC receives the request for vehicle deceleration from the Active Cruise Control via the PT-CAN. DSC reduces the speed. To do this, DSC intervenes in the brake system. (goal: comfortable vehicle deceleration. No DSC intervention in the sense of enhanced operating stability.) With automatic braking, the brake lights are actuated depending on the vehicle deceleration and the gradient of the road (legally prescribed).
7. FPM: Accelerator pedal module The accelerator pedal module signals the driver's command. This signal is required to check the respective driving status. (evaluation via DME/DDE) By pressing the accelerator pedal, the speed setpoint of the Active Cruise Control can be overridden at any time.
8. Brake light switch The brake light switch tells the Active Cruise Control when the brake pedal has been pressed. Active Cruise Control is deactivated if braking actions are necessary.
9. Clutch module (manual transmission only) Clutch engagement/disengagement is recognized by the signal from the clutch module. During the clutch engagement/disengagement process, the engine speed is maintained at an optimal speed range by the DME or DDE. After the clutch has been reengaged, the DME/DDE will adjust back to the current torque request from the Active Cruise Control. If the engine speed is too high or too low, an audible signal and a Check Control message prompt the driver to change gear. The prompt to upshift when the engine speed is too high is only made during the warm-up phase of the engine. If no gearshift or change in engine speed is made within approximately 5 seconds of such a signal being given, Active Cruise Control will be deactivated. If the clutch is disengaged for longer than about 6 seconds, Active Cruise Control (ACC) will be deactivated. Active Cruise Control cannot be activated in 1st gear. Active Cruise Control is automatically deactivated in the "neutral gate" (i.e. no gear engaged and clutch not depressed).

1. EGS and SMG: electronic transmission control and sequential manual transmission Electronic transmission control The electronic transmission control evaluates the data from the DME/DDE and ACC sensor. The adaptive transmission control (constituent component of electronic transmission control) adapts the shift characteristics of the driving program to the driver's commands and the driving situation. Sequential manual transmission No automatic upshift in manual mode. In order to prevent excessively high engine speeds, an audible signal and Check-Control message prompt the driver to change gear. The prompt to upshift when the engine speed is too high is only made during the warm-up phase of the engine. The following data is transmitted from the ESG or SMG to the ACC sensor: gear engaged status information about gearshifts The ACC sensor transmits the following data to the EGS/SMG: current operating status current torque request
2. LM: Light module When Active Cruise Control is in operation, the brake lights are actuated during automatic braking (legal requirement). This requires a signal sent via the K-CAN to the light module. Active Cruise Control uses the "turn signals" signal from the light module for assistance when changing lanes. In other words, if a left turn signal is given before overtaking, the distance to the vehicle in front is reduced. The vehicle to be overtaken is "ignored" more easily. Conversely, when you move back into the right lane, vehicles being driven there will be monitored more quickly.
3. SZL: Steering column switch cluster The SZL processes all data from the cruise-control system steering-column stalk. > E65, E66 as well as E60, E61, E63, E64 before 09/2005 The SZL is connected to the safety and gateway module (SGM) via the byteflight . The SGM creates the connection to the bus system. The SGM connects the SZL with the remaining buses. > E60, E61, E63, E64 from 09/2005 The SZL is connected to the bus system via the PT-CAN.
4. Displays in the instrument cluster For Active Cruise Control, the following displays are available in the instrument cluster: Set speed via an indicator disc (Set speed = selected km/h of the cruise control system) Monitored vehicle (Display through lit up icon) Request for action to driver (Display through flashing icon. In addition, an audible warning is made.) Selected distance from vehicle driving ahead (Display via icon) The LCD display briefly shows the newly selected set speed (approximately 6 seconds). Check-Control message in LCD display
5. M-ASK or CCC and CID: Multi-audio system controller/Car Communication Computer and Central Information Display > E60, E61, E63, E64 only For the instrument cluster, the M-ASK and CCC serve as an interface to the Central Information Display (CID). Amongst other things, the CID displays detailed information about the Check-Control messages. To back up the Check-Control message, the M-ASK /CCC emit audible warnings through the loudspeakers (depending on national version). The instrument cluster assumes control over these warnings via the K-CAN. CCC with Professional navigation system option 609: Only in the combination of CCC with Professional navigation system option 609 are the additional scopes of operation possible for the dynamics control behavior.
6. CD: Control Display > E65, E66 only The Control Display is the central display for the information and communication system. The Control Display is used as an interface between the MOST and K-CAN data buses. (MOST stands for "Media Oriented System Transport"; K-CAN stands for "Body Controller Area Network".) Amongst other things, the Control Display displays detailed information about the Check-Control messages. The instrument cluster controls these warnings by means of the K-CAN.
7. CAS: Car Access System The CAS provides input signals relating to terminal status (e.g. terminal 15 ON).
8. HUD: Head-up display > E60, E61, E63, E64 only The Head-up display (option 610) displays the following information: Set speed Object ahead monitored Request for action to driver Timed separation setting Check-Control messages

ACC Sensor With Control Unit: E60, E61, E63, E64, E65, E66

Installation location

The ACC sensor with control unit is installed in the front of the vehicle, under the bumper.

Scheme 8

Design

Scheme 9

Pin assignments

PIN ASSIGNMENTS FOR CONNECTOR X1783, 8-PIN

How it works

The Active Cruise Control option can be activated from speeds of 30 km/h upwards.

The ACC sensor is always activated once a speed of approximately 15 km/h has been reached (standby for activation). This means that cruise control is ready for immediate action when it is switched on.

Scheme 10

The ACC sensor senses the monitoring range in front of the vehicle with 4 radar beams.

The monitoring range is between approx. 2-120 meters.

The transmission frequency of the ACC sensor is approx. 76 GHz. This means the sensor range is constantly monitored.

The sensor range is limited laterally and in height by the opening angle of the ACC sensor

1. Horizontal opening angle: +/-8°
2. Vertical opening angle: +/-4°

Each radar beam is emitted by an antenna which also receives the reflected radar beams.

Measurement of distance and relative speed

The ACC control unit determines the distance and relative speed from the frequency spectrums as follows

1. The distance is calculated from the time lag of the frequency spectrums.
2. The relative speed is calculated using the Doppler effect. The Doppler effect is a law of physics: if the object is moving towards the transmitter, the frequency of the reflected radar wave will be higher. If the object is moving away from the transmitter, the frequency of the reflected radar wave will be lower.

Scheme 11

Determination of the angle

If an object is in the monitoring range, the reflected radar waves are received depending on the angle between the wheel axis and the object

The 4 antennae receive different amplitudes.

Example of how to determine the angle

The diagram shows the vehicle with its 4 radar beams.

The vehicle ahead is in the range of radar beams 3 and 4.

Scheme 12

Steering Column Stalk For Active Cruise Control: E60, E61, E63, E64, E65, E66

Installation location

Active cruise control (ACC) is operated with the lower left-hand stalk on the steering column.

How it works

Scheme 13

The signals from the steering-column stalk are processed by the steering column switch cluster (SZL).

The following signals are transmitted by the cruise-control system steering-column stalk to the SZL

1. Active cruise control activated/not activated
2. Set speed selected anew or changed
3. Timed separation changed

The range of adjustments for Active Cruise Control are described in the Owner's Handbook.

Active Cruise Control Displays In Instrument Cluster: E60, E61, E63, E64, E65, E66

Installation location

All relevant displays for Active Cruise Control are in the instrument cluster.

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Scheme 15

How it works

The check control messages show information and warnings to Active Cruise Control.

The check control messages are displayed in the LC display.

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Scheme 17

System functions

The system functions of the Active Cruise Control option are described below

1. Monitor object ahead
2. Cruise control
3. Lens heating
4. Low-voltage cutout and high-voltage protection for ACC sensor
5. Self-diagnosis and compensation for minor horizontal adjustments
6. Influence on the dynamics in connection with a navigation system
7. System limits Monitor object ahead Objects are all vehicles in the same lane. The vehicles in other lanes are of no interest for the Active Cruise Control option. In the same lane, the vehicle immediately ahead is selected as the object. With the calculated expected same lane, the lateral deviation of each monitored object to the same lane can be determined. The radar waves received cannot distinguish between animals, vehicles and traffic signs. In order to prevent incorrect reactions, stationary objects and traffic in the other direction are ignored in the distance control.

The Active Cruise Control option differentiates between 2 driving conditions

1. Cruise control with specified set speed A selected set speed (in the range 30 km/h - 180 km/h) is automatically maintained on open roads without vehicles driving ahead.
2. Cruise control with speed adapted to that of vehicle driving ahead If a slower vehicle is detected in the vehicle's own lane, the vehicle's own speed will be adapted to that of the vehicle driving ahead. At the same time, a distance from this vehicle preset by the driver is established (4 fixed, timed separations can be selected). The timed separation from a vehicle driving ahead is no less than 1 second under stationary conditions. In certain conditions (e.g. when a vehicle cuts in a short distance ahead), this timed separation may briefly be less than 1 second.

Lens heating

The lens of the ACC sensor is made of plastic. The built-in lens heating ensures better availability of the Active Cruise Control option in winter weather conditions.

The lens heating is activated by the ACC sensor. The heating is controlled via a pulse-width modulated signal (PWM signal). The heating coil is integrated into the lens of the ACC sensor

The lens heating is only activated within a certain ambient temperature range (approximately +5 °C to -5 °C). Reason: Only at temperatures around zero is snow wet or moist. At temperatures well below this, snow will be dry. To prevent snow from thawing on the lens and creating an artificial coating, the heating is switched off below a certain ambient temperature. The current ambient temperature value is transmitted by the instrument cluster.

1. Conditions for activation Engine ON ACC ON Ambient temperature between -5 °C and +5 °C
2. Safety cutout Temperature in ACC sensor over 50 °C (measured by interior temperature sensor in ACC sensor control unit) Voltage greater than 16 volts The safety cutout shuts down the lens heating. The Active Cruise Control option remains activated. (No fault memory entry)
3. Monitoring The lens heating is monitored for open and short circuits in the heating coil. If the monitoring reports a fault, the Active Cruise Control option will be shut down. (Fault memory entry)

Low-voltage cutout and high-voltage protection for ACC sensor

The ACC sensor works with a supply voltage of 9 to 16 volts.

1. Low-voltage cutout If the on-board supply voltage drops below about 9 volts, the ACC sensor will perform a low-voltage cutout and a fault memory entry will be stored. The ACC sensor will be reactivated when the on-board supply voltage exceeds 9.8 volts again.
2. Overvoltage protection

If the on-board supply voltage exceeds about 17.5 volts, the ACC sensor will perform a cutout with a fault memory entry.

The ACC sensor will be reactivated when the on-board supply voltage drops below 17.0 volts again.

Self-diagnosis and compensation for minor horizontal adjustments

External forces may change the alignment of the ACC sensor. A horizontal change leads to function limitations. (Function limitations encountered are, e.g.: reaction to vehicles in the next lane or late reaction to vehicles in the same lane).

Self-diagnosis allows the ACC sensor to compensate for minor horizontal adjustments of up to 1°.

If a horizontal adjustment of more than 1° is detected, the Active Cruise Control option will be deactivated and a fault will be stored in the fault memory. A Check-Control message will be issued.

Influence on the dynamics in conjunction with a navigation system

If the Active Cruise Control is coupled with a navigation system, this may have an influence on the dynamics. (Only possible in combination of CCC with the Professional navigation system option 609.)

Navigation systems provide additional information, such as the course of the road and the road category.

The road category is split up as follows

1. Motorways and well finished fast roads (faster acceleration)
2. Main roads and highways (average acceleration)
3. Urban driving (reduced acceleration)

On motorways and well finished fast roads, Active Cruise Control is expected to be highly dynamic. In other words, faster acceleration if the driving mode changes from following a car ahead to clear road ahead. The set speed is adjusted quickly.

On main roads and highways, Active Cruise Control is expected to be averagely dynamic. In other words, comfortable acceleration if the driving mode changes from following a car ahead to clear road ahead. The set speed is adjusted with an average acceleration behavior.

During urban driving, a reserved dynamic is expected of the Active Cruise Control. In other words, reduced acceleration behavior if the driving mode changes from following a car ahead to clear road ahead. The set speed is adjusted moderately.

The often difficult traffic situations during urban driving make reduced acceleration behavior necessary.

In addition, the number of bends on the road ahead is analyzed and the dynamic of the Active Cruise Control adjusted accordingly.

System limits

If the limit of the functional range is reached, the driver is prompted to act (brake or swerve).

During operation, the following system functions requiring explanation (for the driver) can occur due to the limits of the functional range

1. Limited range and deceleration: The range of the ACC sensor is limited (approximately 120 meters). Rain, snow and fog absorb radar waves. This will significantly reduce the range of the ACC sensor. The Active Cruise Control option is only able to effect limited deceleration via the DSC (dynamic stability control) (a maximum of 2.5 m/s 2 ; E65, E66: a maximum of 2.0 m/s 2 ). This means that cruise control is only able to compensate for a limited relative speed. Operation of the Active Cruise Control is only possible in flowing traffic in a road speed range from 30 km/h to 180 km/h.
2. Lateral monitoring range The lateral monitoring range of the ACC sensor is limited, meaning that a monitored vehicle ahead could be lost due to a tight bend. In such cases, cruise control will not accelerate to the set speed for approximately 2 seconds. This will prevent the vehicle from accelerating too close to the vehicle ahead, which is possibly only briefly not being monitored. When driving straight ahead, this can cause a delayed reaction to another vehicle cutting in close in front. The vehicle cutting in will not be monitored by the cruise control until it is clearly in the same lane as the vehicle with the Active Cruise Control option.
3. Display for monitored vehicle does not light up, the vehicle remains below the set speed and does not accelerate further. Causes: On sharp bends, the vehicle's speed will be controlled in such a way that lateral acceleration does not exceed a maximum of 4.0 m/s2 to maintain driving comfort.
4. Timed separation less than 1 second The timed separation from a vehicle driving ahead is no less than 1 second in the adjusted status. In certain conditions (e.g. when a vehicle cuts in a short distance ahead), this timed separation may briefly be less than 1 second. If the deceleration induced by the cruise control is not sufficient, the driver will have to intervene directly.
5. ACC sensor blind If the ACC sensor is blinded, the Active Cruise Control option shuts down. (Blinding, e.g. due to extremely heavy snowfall, through a layer of ice on the sensor or through dirt) Cruise control can be reactivated after the ACC sensor has been cleaned.
6. Bends cannot be detected in an anticipatory manner The cruise control is unable to work in an anticipatory manner when the vehicle is cornering. It is only able to react to existing lateral acceleration when it is already on the bend. For this reason, the driver is responsible for ensuring that an appropriate speed is being driven as the vehicle enters the bend.
7. Active Cruise Control deactivated after DSC intervention or brake application by the driver Cruise control will be deactivated following DSC intervention or a brake application by the driver. (DSC intervention in the sense of enhanced operating stability.) Cruise control will then have to be reactivated at the cruise control steering-column stalk.

Operation

Operation of the Active Cruise Control option is described in the Owner's Handbook.

US and CDN national versions

Different timed separations encoded for following mode (1.5 - 1.8 - 2.2 - 2.5 seconds)

US and GB national versions

Active Cruise Control controls between 20 mph and 110 mph.

Speed preselections are possible in increments of 1 mph and 5 mph.

Subject to change.

Scheme 18

Park Distance Control (PDC) is an item of special equipment (option 508). Park Distance Control (i.e.: parking-aid) supports the driver in maneuvering in tight spaces.

For the BMW 5-Series (E60, E61) and the BMW 6-Series (E63, E64), the PDC was taken from the E65.

On the E60 PDC has the following new features

1. The PDC button is in the center console switch cluster. The signal from the PDC button is transferred to the PDC control unit through the K-CAN.
2. The signal from the reverse-light switch (reverse gear engaged) on vehicles with manual transmission is transferred from the light module to the PDC control unit via the K-CAN.
3. Display form of the optical warnings on the Central Information Display (display image). The PDC measures the distance to objects within its range with ultrasonic sensors. For more information, refer to «E60, E61, E63, E64 - PARK DISTANCE CONTROL (PDC) SYSTEM OVERVIEW»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__e60-e61-e63-e64-park) . The driver is warned of an object that could cause a collision as follows
4. Acoustic warning (via multi-audio system controller, M-ASK, and mid-range loudspeaker)
5. Visual warning (via Central Information Display)

The PDC uses these two 2 warning functions to offer a degree of comfort for drivers who are hard of hearing or physically impaired.

A fault in the PDC is indicated by a Check-Control message.

E60, E61, E63, E64 - Park Distance Control (PDC) system overview

Inputs/outputs

Scheme 19

Scheme 20

System circuit diagram

Scheme 21

PDC consists of the following components

1. 8 ultrasonic sensors There are 4 ultrasonic sensors in each of the front and rear bumpers. The ultrasonic sensors emit ultrasonic impulses. These ultrasonic impulses are reflected by obstacles (echo impulses). The ultrasonic sensors receive and amplify these echo impulses. The amplified echo impulses are then converted into a digital signal. Each ultrasonic sensor has its own microprocessor, its own power supply and its own data connection to the PDC control unit. For more information, refer to «E60, E61, E63, E64 - PARK DISTANCE CONTROL ULTRASONIC SENSORS»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__e60-e61-e63-e64-park) .

Note. Cleaning the ultrasonic sensors. To make sure the system remains fully operational, keep the ultrasonic sensors clean and free from ice. Do not clean by spraying high-pressure washers directly at the ultrasonic sensors. When cleaning, always maintain a minimum distance of at least 10 centimeters.

1. PDC button The PDC button is in the center console switch cluster. The signal from the PDC button is transferred through the K-CAN to the PDC control unit. The PDC button is used to manually switch the Park Distance Control system on and off. When the PDC is switched on, the function LED in the PDC button lights up. If a fault develops in the PDC, the function LED in the PDC button flashes.
2. PDC control unit The PDC control unit controls the ultrasonic sensors for transmitting ultrasonic impulses. The PDC control unit also receives the digital signals from the individual ultrasonic sensors. By comparing the individual digital signals, the PDC control unit calculates the minimum distance between the ultrasonic sensor and the object. When an object is detected, an acoustic warning and a visual warning are given. For more information, refer to «E60, E61, E63, E64 - PDC CONTROL UNIT»(/bmw/m6/e63e64-2005-2010/remont/collisionavoidance/#distance-systems-cruise-control-service-information__e60-e61-e63-e64-pdc) . The PDC control unit is connected to various other control units via the bus systems
3. Multi-audio system controller / Car Communication Computer The multi-audio system controller (M-ASK) or Car Communication Computer (CCC) emits the PDC acoustic warning through the mid-range loudspeakers.
4. Central Information Display The visual PDC warnings are given in the Central Information Display (CID). In addition, information regarding a Check-Control message that may be present is shown.
5. Instrument cluster A current Check-Control message is indicated by a symbol in the LCD display in the instrument cluster. Moreover, the instrument cluster also provides the exterior temperature and the kilometer reading for the PDC control unit. Ice and frost can cause an unexpected response from the ultrasonic sensors. The response characteristics of the ultrasonic sensors changes depending on the exterior temperature. If a fault is stored in the fault memory, the kilometer reading and the exterior temperature are also stored.
6. DSC control unit The DSC control unit supplies the PDC with information about the roadspeed and distance travelled.
7. Electronic transmission control On vehicles with automatic transmission, the electronic transmission control (ESG) supplies the signal that reverse gear is engaged.
8. Light module On vehicles with manual transmission, the light module (LM) supplies the signal that reverse gear is engaged.
9. Car Access System The CAS control unit supplies the PDC with the terminal status (e.g.. terminal 15). For vehicles from 03/2004, power is supplied to the PDC control unit through terminal 30g (active) instead of terminal 15.
10. Trailer module (AHM)

The trailer module sends a signal indicating whether or not the vehicle is towing a trailer. If a trailer is recognized, the acoustic and visual warnings for the rear bumper are deactivated.

E60, E61, E63, E64 - Park Distance Control Ultrasonic Sensors

Installation location

There are 4 ultrasonic sensors in each of the front and rear bumpers (illustration shows E60).

Scheme 22

Construction

Compared to earlier systems, the ultrasonic sensors have a circular membrane (larger effective range and lower sensitivity to moisture). The membrane is always painted in the vehicle's body color.

The ultrasonic sensors in the front and rear bumpers are electrically identical. The difference between the front and rear ultrasonic sensors is the arrangement of the plug connection, which is due to the specific installation location.

How it works

The ultrasonic sensors are activated by the PDC control unit, either in combined transmit and receive mode or in pure receive mode.

1. Combined transmit and receive mode In combined transmit and receive mode, the 8 ultrasonic sensors first transmit a package of ultrasonic impulses. Each ultrasonic sensor then receives the echo pulse reflected by an object within the effective range. This echo pulse is amplified in the ultrasonic sensor and sent to the PDC control unit in the form of a digital signal. The PDC control unit calculates the distance from the object from the time lag of the echo pulse.
2. Receive mode In receive mode, the ultrasonic sensor receives the echo pulses transmitted by the adjacent ultrasonic sensors. The PDC control unit is then able to evaluate the signals of up to 3 ultrasonic sensors (triangulation). The evaluation of these signals from several ultrasonic sensor is used to calculate the minimum distance between the vehicle and the object.

E60, E61, E63, E64 - PDC Control Unit

Installation location

On the BMW 5-Series, the PDC control unit is located under the spare wheel in the luggage compartment well. The PDC control unit is fitted in the function carrier (illustration shows E60).

On the BMW 6-Series, the function carrier is in front of the battery in the luggage compartment well.

Scheme 23

Construction

The PDC control unit is connected to the rest of the vehicle electrical system by 3 plug connectors.

Pin assignment for X300, 12-pin

PIN ASSIGNMENT FOR X300, 12-PIN

Pin assignment for X18013, 18-pin

PIN ASSIGNMENT FOR X18013, 18-PIN

Pin assignment for X18362, 18-pin

PIN ASSIGNMENT FOR X18362, 18-PIN

PDC incorporates the following functions

1. Acoustic warnings
2. Visual warnings
3. Check Control Acoustic warnings The acoustic warnings are emitted by the M-ASK via the mid-range loudspeaker. If an object is detected by 2 ultrasonic sensors, the loudspeaker closest to the object is actuated. The mid-range loudspeaker in the left/right-hand front doors or the midrange loudspeaker on the left/right-hand sides of the rear shelf can be actuated. If an object is detected by 3 ultrasonic sensors, the mid-range loudspeakers on the left and right-hand sides are actuated together. The smaller the distance to the object, the faster the sequence of acoustic warning tones. A distance of less than approx. 25 centimeters is indicated by a continuous tone. The warning tone switches off as soon as the vehicle moves away from the object. If the vehicle is moving directly towards a wall, the acoustic warning tone will be switched off after approx. 3 seconds so that it does not distract the driver. If the vehicle continues to approach the wall, the warning will be reactivated. Effective range for acoustic warnings: approx. 60 centimeters for the ultrasonic sensors at the two corners of the front bumper approx. 70 centimeters for the two middle ultrasonic sensors in the front bumper approx. 60 centimeters for the ultrasonic sensors at the two corners of the rear bumper approx. 150 centimeters for the two middle ultrasonic sensors in the rear bumper Visual warnings The visual PDC warnings are given in the Central Information Display (CID). This is subject to the display in the CID being active. The visual warnings are given earlier than the acoustic warnings. The effective range is approx. 2 meters at the front and approx. 2.5 meters at the rear. The graphic display is shown on the CID. The PDC control unit supplies the distance between the ultrasonic sensor and the object detected via the K-CAN. The display on the CID is an overhead view of the vehicle with the effective ranges of the ultrasonic sensors. The distance to objects detected is shown in the colors of traffic lights: Distance down to 100 centimeters: green Distance between 100 an 50 centimeters: yellow Distance less than 50 centimeters: red The display appears as soon as the PDC is switched on (manually or automatically). The display overrides other displays in the CID. When the PDC is switched off again, the previous display automatically appears again in the Central Information Display. Check Control If a fault develops in the PDC, the function LED in the PDC button flashes. In this situation, PDC cannot be switched on. At the same time, a Check-Control message is displayed in the following form Symbol in the LCD display in the instrument cluster The following text appears in the status line of the Central Information Display: "PDC failure!" In the menu "BMW Service", the following text can be called up in the submenu "Check-Control messages": "Park Distance Control No acoustic warning available for Park Distance Control (PDC). Have the problem checked by BMW Service as soon as possible."

Conditions for switching on and off

PDC is switched on under the following conditions

1. PDC button pressed (PDC switched on manually)
2. Reverse gear engaged (PDC switched on automatically) PDC is switched off under the following conditions
3. PDC button pressed (PDC switched off manually)
4. Ignition switched off (PDC switched off automatically
5. After driving approx. 50 meters
6. After exceeding a speed of 30 km/h

When a trailer is being towed, the acoustic and visual warnings for the rear bumper are deactivated.

For this to happen, the trailer must be electrically connected to the vehicle.

Problematic conditions for switching on and off

In borderline situations, PDC may give a warning even though there is no object within the effective range (reflection from the ground, e.g. on coarse gravel).

In borderline situations, it could happen that objects that are present are not detected (no or insufficient reflection due to geometric form).

Under the following conditions, it could happen that the PDC gives a warning, even though there is no object within the effective range

1. Ultrasonic sensor incorrectly located in its bracket
2. Heavy rain
3. Severe dirt contamination or icing of the ultrasonic sensors
4. Ultrasonic sensors covered in snow
5. Echo pulses caused by ground, e.g. extremely coarse road surface or high grass
6. Very smooth walls in large, enclosed, rectangular spaces, e.g. in underground car parks (interference from earlier, reflected echo impulses) Under the following conditions, the PDC may not recognize an obstacle that is present
7. Low objects or objects with corners and sharp edges (no reflection)
8. If you drive alongside a wall while you are parking, the acoustic warning will be deactivated so long as you are moving parallel to the wall.

The visual warning (display) is switched on in the Central Information Display (CID) as follows

1. "Settings (i)" menu
2. "Vehicle settings" menu
3. "PDC" menu
4. Activate "Display on"

Japanese national version

So long as reverse gear is engaged, an acoustic signal (reversing gong) is given via the multi-audio system controller (M-ASK) and the mid-range loudspeaker. The reversing gong is deactivated immediately if the PDC detects an object in the effective range and emits its own acoustic warning.

Subject to change.

See also:
• SYSTEM OVERVIEW FOR ACTIVE CRUISE CONTROL: E60, E61, E63, E64 UP TO 09/2005
• ACC SENSOR WITH CONTROL UNIT: E60, E61, E63, E64, E65, E66
• STEERING COLUMN STALK FOR ACTIVE CRUISE CONTROL: E60, E61, E63, E64, E65, E66
• ACTIVE CRUISE CONTROL DISPLAYS IN INSTRUMENT CLUSTER: E60, E61, E63, E64, E65, E66
• E60, E61, E63, E64 - PARK DISTANCE CONTROL (PDC) SYSTEM OVERVIEW
• E60, E61, E63, E64 - PDC CONTROL UNIT