Electrical error on CAN1 sub-bus (BusOff) CAN1 is TMS Sub-bus except for Battery slave units (BSU:s) where CAN1 is BMU Sub-bus.
• Measure the resistance on the connector to E81 (with the 24V battery disconnected) between CAN-high (pin B29) and CAN-low (pin B32). It should be close to 60 ohm (one 120 ohm termination resistor in each end of the CAN-bus). • Measure the resistance on the connector to E81 (with the 24V battery disconnected) between CAN-high (pin B29) and supply. It should be high ohmic (Mega ohm). • Measure the resistance on the connector to E81 (with the 24V battery disconnected) between CAN-high (pin B29) and ground. It should be high ohmic (Mega ohm). • Measure the resistance on the connector to E81 (with the 24V battery disconnected) between CAN-low (pin B32) and supply. It should be high ohmic (Mega ohm). • Measure the resistance on the connector toE81 (with the 24V battery disconnected) between CAN-low (pin B32) and ground. It should be high ohmic (Mega ohm). • Disconnect one ECU unit at the time from the sub-bus and check if the fault disappears.
What you'll see
No driver-visible symptom recorded.
System reaction
• VOR, the hybrid system will not work since the battery will not be engaged. The DCC will not receive VCB-power and the 24-volt system will drain the 24-volt batteries. • Amber warning lamp "24V batteries not charged" and "Hybrid System Fault" is shown in ICL
Diagnostic depth
The DTC is set to active if CAN controller of the sub-bus is in the state bus-off. The DTC is set to inactive if the CAN-controller is not in state bus-off for 1100 ms. The DTC is not validated (stored) if: • the ignition is turned off • first 2 seconds after ignition on • the supply voltage is below 22 volt • the supply voltage is above 32 volt
• Defect wiring of the sub-bus: - short circuit between CAN-high and CAN low. - short circuit between CAN-high and supply voltage. - short circuit between CAN-high and ground. - short circuit between CAN-low and supply voltage. - short circuit between CAN-low and ground. • Defect ECU unit(s) on the sub-bus.