- This CAN bus requires external terminating resistors.
- The terminating resistors can be located in control units or voltage distributors depending on the CAN bus.
Legend and description for figure 1CAN-H: CAN bus HighCAN-L: CAN bus LowECU 1 ... n: Control unit 1 ... nCAN terminating resistor (
Example: 120ohms)Legend and description for figure 2U 1: Specification approx. 3,6 voltsU 2: Specification approx. 2,5 voltsU 3: Specification
approx. 1,4 voltsContinue with button F2
1.1.1.3.2. No further information available.
1.1.1.4. Possible aids and their usage
Evaluation of CAN fault codes
- The control units present in the vehicle (actual configuration) are compared with the coding in control unit CGW (specified configuration).
- Filtering and evaluation of all CAN timeout fault codes present in the vehicleThe result of the evaluation leads to the required test steps.
Multimeter
- Aids for voltage and resistance measurement in menu item 'Measurements with multimeter on CAN network'
Measuring system
- Aid for graphic representation of CAN signal and voltage levels
- The specified characteristics shown in Measurement Technology are used to recognize changed CAN voltage levels, which can be caused by
faulty CAN components.
- Possible procedure: Disconnect and then reconnect the CAN bus subscribers at the voltage distributor one at a time.Compare the pass image
with the actual image from the oscilloscope.
Star Diagnosis CANtool
- Aids for representation of actual values and identification of bus wake-up events and bus keepawake events
Continue with button F2
1.1.1.4. No further information available.
1.1.2. Read current CAN configuration and CAN fault codes
Warning!Communication with ECU required.
1.1.3. Further CAN test options
