IBU CAN node timeout
• Check the BMU(E81) for DTCs regarding the IBU • Check that the battery pack connector (E83) is connected to the battery • Measure that the unit has correct supply voltage on E83 pin 1 harness side • Measure that the unit has correct ground connection on E83 pin 3 harness side • Measure that the unit has correct wake-up signal on E83 pin 2 harness side • Measure the resistance on the battery CAN-bus on the BMU(E81) between pins B11 CAN_H and B14 CAN_L with the battery pack (E83) connector disconnected. It should be approximately 120 ohm (one 120 ohm termination resistor in each end of the CAN-bus, but one is disconnected in this measurement) • Dismount the battery pack according to the instruction in multi • Change the IBU according to instruction in multi NOTE! Replacing the IBU is considered an electrical work and shall only be performed by Scania certified personnel. Vehicle shall be made safe according to electrical work procedure.
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 active if CAN message from the IBU has been absent for 200 ms. The DTC is set inactive when IBU CAN message is received. The DTC is not set in the following cases: • ignition is turned off • first 2 seconds after ignition on • system voltage is below 22 volt • system voltage is above 32 volt • short circuit or open circuit on the Hybrid batt-bus (separate DTCs)
• Power supply to IBU has failed • Wake up signal to IBU has failed • IBU unit disconnected from the batt bus • Faulty IBU unit