Checking the CAN bus cable
Tools:
88890074 Multimeter
88890016 Break-out cable
9998699 Break-out box
The resistance of the CAN bus termination resistors,
one 120 Ω
resistor in the ECU and one 120 Ω resistor
in the cable harness, are measured.
1 NOTICE! Cut the current with the main switch.
2 Disconnect the 8-pin Deutsch connector at the
DCU or disconnect at the CIU.
3 Use multimeter 88890074 to do resistance meas-
urement towards the EMS 2.
Measurement points
in the engine connector
at the DCU
Nominal value
1–2 U ≈ 60 Ω
or
Measurement points
in the CIU connector
Nominal value
11–12 U ≈ 60 Ω
NOTICE!
Even if the measured value equals the nom-
inal value the data bus cable could be faulty due to
short circuit between a data bus cable and another
cable in the harness.
1
Connect break-out cable 88890016 with break-out
box 9998699 between the EMS 2 and the CIU/
DCU.
2 Use multimeter 88890074 to do a voltage meas-
urement.
Measurement points
in the measurebox
Nominal value
16 – 17 (between CAN
bus)
U ≈ 2.3 V – 2.7 V
NOTICE! Even if the measured value equals the nom-
inal value the data bus cable could be faulty due to
short circuit between a data bus cable and another
cable in the harness.
30-2 Fault Tracing
186 47701632 10-2013 © AB VOLVO PENTA