CAN 1 - Hardware CAN bus off
|  | Description
|  | Effects on the driving operation
|  | Possible causes
|  | Connector pin assignment of transmission control unit
|  | Place of action
|  | Troubleshooting
|  | Instruction
|  | Setting conditions of the event
|  | Test conditions of the event
|  | Final function check
|  | See also:
Description Communication on the CAN bus fails due to CAN ´bus off´ conditions. 'bus off' : If the error counter of a CAN controller exceeds the value 255, the CAN controller will assume the 'bus off' status. The CAN controller is disconnected from the CAN bus using an internal logic function and does no longer participate in the bus activities. CAN messages can no longer be received nor sent. Effects on the driving operation No CAN communication via CAN controller 1 of the transmission control unit possible. Vehicle does not drive or only with restrictions. Possible causes Short-circuit between CAN1-H and CAN1-L or short-circuit of a CAN1 line to ground. * A bus node is sending with incorrect bit rate. * Another defective control unit is connected to the CAN1 bus. * Defective CAN1 transceiver in the E300 control unit. Connector pin assignment of transmission control unit
Pin | Stecker A | Stecker B | Stecker C | Stecker D
1 | SHIELD | EK | FLEXI-1 | -BATT
2 | TIM+ | DK | --- | IGN
3 | TIM- | SK | FLEXI-3 | FLEXI-11
4 | N1+ | RBK | FLEXI-4 | K-LINE
5 | N1- | TB | FLEXI-5 | CAN1-H
6 | N2+ | --- | FLEXI-6 | CAN1-H
7 | N2- | RBG | FLEXI-7 | CAN-SHLD
8 | N3+ | PB | FLEXI-8 | CAN1-L
9 | N3- | WR | FLEXI-9 | CAN1-L
10 | --- | WP | FLEXI-10 | CAN2-H
11 | --- | --- | FLEXO-2H | CAN2-H
12 | EKM | FLEXI-12 | FLEXO-4H | CAN2-L
13 | DKM | S-GND | FLEXO-3H | CAN2-L
14 | SKM | OIL-LVL | FLEXO-5L | CAN1-R
15 | PBM | T-SUMP | --- | ---
16 | TBM | --- | --- | FLEXO-1L
17 | RBKM | T-CONV | --- | CAN2-R
18 | MVM-GND | MV-GND | --- | +BATT
Place of action CAN bus Troubleshooting
|  | NOTE The following service work may only be performed by persons who are authorised by the vehicle manufacturer: Loading software and/or datasets into the transmission control unit. Service work at vehicle components which are not included in the VOITH delivery.
Instruction Measure resistance between CAN1-H and CAN1-L ( ~ 60 Ohm ). Check cabling. * Measure resistance between CAN-H1 and CAN1-L to ground: The resistance must lie well above 1 kohm. * Check whether the correct dataset and correct CAN1 protocol are active. * Disconnect all control units from the CAN1 bus one after the other and check whether this eliminates the fault. * Replace E300 control unit. Setting conditions of the event No description available. Test conditions of the event No description available. Final function check If the defective component cannot be clearly identified, you should try to reproduce the fault: Reinstall the component in the vehicle. Test the function. After the fault has been eliminated, the following steps have to be carried out: Conduct a test drive with function check. Read out the fault memory. Check the transmission for leaks. Perform a final visual inspection. These steps are necessary to ensure the entire vehicle functions. See also:
|  | Aftersales service index
© by Voith Turbo GmbH & Co. KG, S. Brunnengräber send remarks to stefan.brunnengraeber@voith.com (documentation department)