Description

A 'CAN bus off' has been detected.

The CAN controller has detected that there are no other bus nodes on the CAN bus.

Effects on the driving operation

Driving is not possible or restricted.

Possible causes

The control unit has no connection to the other bus parties.

Function of the safety computer

The safety computer (S-CPU) monitors safety-relevant signals which the function computer (F-CPU) sends or receives. If the safety computer detects an inadmissible condition, it initiates a reset of the function computer. During that time, the transmission system is in a safe mode (neutral).

Driving operation is only released if both the function computer AND the safety computer give their approval simultaneously. After the release the safety switch in the transmission control unit is closed and the ground of the solenoid valves is connected to the battery ground. Only then can the solenoid valves be activated and enable driving operation.

Place of action

No description available.

Troubleshooting

Check terminating resistors. Check CAN bus including all bus nodes.

If the fault cannot be eliminated, please contact the VOITH customer service.

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:

		CAN 2 - Hardware Occurrence of a bus-off state
		Aftersales service index