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en:artikel:bcm:start [Fri. 01.02.2019 16:36]
jphid
en:artikel:bcm:start [Fri. 01.02.2019 16:37] (current)
jphid [Checks and maintenance]
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 With the help of a CAN bus adapter (e.g. a [[artikel:​elm327-adapter:​varianten]]) a connection with the CAN bus can be established and the transmitted messages can be read. With the help of a CAN bus adapter (e.g. a [[artikel:​elm327-adapter:​varianten]]) a connection with the CAN bus can be established and the transmitted messages can be read.
  
-For example, the reverse gear switch signal can be emulated very nicely. In order to do this, look for ID 433, fourth byte (D3) in a CAN bus analyzer (e.g. [[artikel:​can-bus:​canhacker]]). The second bit in this byte (bitmask 0b00000010) corresponds to the R signal. When not active (input to the BCM not connected and thus driven high (+12V) by the internal pull-up) the bit will have value of 0 (the decimal value of the complete byte will be 0). If the pin 29 of connector C1 (FL) is connected to ground, the bit will take a value of 1 (the decimal value of the complete byte will them be 2). At the same time, a voltage of 12V can be measured at pins 73 and 74 of connector C2. These are the outputs that control the backup lights.+For example, the reverse gear switch signal can be emulated very nicely. In order to do this, look for the fourth byte (D3) of the message with ID 433 in a CAN bus analyzer (e.g. [[artikel:​can-bus:​canhacker]]). The second bit in this byte (bitmask 0b00000010) corresponds to the R signal. When not active (input to the BCM not connected and thus driven high (+12V) by the internal pull-up) the bit will have value of 0 (the decimal value of the complete byte will be 0). If the pin 29 of connector C1 (FL) is connected to ground, the bit will take a value of 1 (the decimal value of the complete byte will them be 2). At the same time, a voltage of 12V can be measured at pins 73 and 74 of connector C2. These are the outputs that control the backup lights.
  
 ===== Repair, update and tuning ===== ===== Repair, update and tuning =====
  
  
  • en/artikel/bcm/start.txt
  • Last modified: Fri. 01.02.2019 16:37
  • by jphid