BMW I01, Информация о продукте

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I01�High-voltage�Components
3.�Electric�Motor
41
Service�information
The�EME�control�unit�performs�several�self-diagnosis�functions�in�order�to�ensure�the�proper�function
of�the�parking�lock�module�and�to�protect�the�components�against�damage.�These�self-diagnosis
functions�are:
• Monitoring�of�lines�for�the�electric�motor,�the�position�sensors�and�the�solenoids�for�short
circuit�against�ground�and�supply�voltage,�as�well�as�for�open�circuit
• Monitoring�of�the�current�level�for�the�electric�motor�with�regards�to�the�maximum�value�and
plausibility�for�the�signals�of�the�position�sensors
• Monitoring�of�the�signals�of�the�position�sensors�(pulse-width�modulated�signal�in�the
specified�range�and�plausibility�of�both�signals�to�each�other).
If�one�of�the�self-diagnosis�functions�identifies�a�fault,�in�the�EME�control�unit�an�entry�is�made�in�the
fault�memory�which�can�indicate�the�fault�cause.�Depending�on�the�severity�of�the�identified�fault�the
parking�lock�will�either�work�again�or�remain�in�the�current�position.�In�each�case,�however,�a�fault�code
entry�is�generated�and�the�customer�is�requested�by�a�Check�Control�message�to�have�the�vehicle
checked�by�BMW�Service.
If�the�cause�for�a�malfunction�cannot�be�determined�using�the�fault�code�entry,�the�Service�employee
can�perform�the�following�checks�and�thus�pinpoint�the�cause:
• Check�the�voltage�supply�of�the�electric�motor�at�the�output�of�the�electrical�machine
electronics�with�a�measurement
• Check�the�wiring�harness�section�for�open�circuit/short�circuit.
The�diagnosis�system�not�only�supports�the�Service�employee�during�troubleshooting�for�the�parking
lock.�The�diagnosis�system�also�offers�Service�functions.�The�most�important�Service�function�is�used
for�the�initialization�of�the�parking�lock.�During�the�initialization�the�electric�motor�in�the�parking�lock
module�approaches�its�end�positions�several�times.�The�signals�of�the�position�sensors�and�also�the
characteristic�of�the�current�level,�which�the�electric�motor�uses,�are�observed.�The�force�which�the
electric�motor�must�apply�and�also�the�current�characteristic�change�through�the�locking�positions�at
the�cam�disc�and�the�force�which�the�fixing�element�exerts.�The�EME�control�unit�uses�these�values�to
calculate�the�positions�at�which�the�parking�lock�is�correctly�engaged�or�disengaged.�The�respective
signal�values�of�the�position�sensors�are�stored�permanently�in�the�EME�control�unit�and�are�available
from�this�time�for�the�control�of�the�operation�of�the�parking�lock.
The�initialization�of�the�parking�lock�in�the�I01�using�the�diagnosis�system�is�necessary�if
• the�transmission�was�replaced,
• the�parking�lock�module�was�replaced�or
• the�electrical�machine�electronics�was�replaced.
If�the�parking�lock�module�is�to�be�replaced,�ensure�that�the�new�part�is�supplied�in�the�position�which
corresponds�to�the�condition�"Parking�lock�disengaged".�Proceed�as�follows�to�install�the�new�parking
lock�module:
1 Secure�the�vehicle�against�rolling�away�using�the�parking�brake