Group 30: Electrical system
Diagnostic Trouble Codes
143
Measurements
Checking the CAN bus cable. 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.
•
NOTE!
Cut the current with the main switch.
•
Disconnect the 8-pin Deutsch connector at the
DCU or disconnect at the CIU.
•
Use multimeter 9812519 to do resistance mea-
surement towards the EMS 2.
Measurement points
Nominal value
in the engine connector
at the DCU
1 – 2
U
≈
60
Ω
or
Measurement points
Nominal value
in the CIU connector
11 – 12
U
≈
60
Ω
NOTE!
Even if the measured value equals the nomi-
nal value the data bus cable could be faulty due to
shortcircuit between a data bus cable and another ca-
ble in the harness.
•
Connect adapter cable 88890016 with measure-
box 9998699 between the EMS 2 and the CIU/
DCU.
•
Use multimeter 9812519 to a voltage measure-
ment.
Measurement points
Nominal value
in the measurebox
16 – 17 (between CAN bus)
U
≈
2.3 V – 2.7 V
NOTE!
Even if the measured value equals the nomi-
nal value the data bus cable could be faulty due to
shortcircuit between a data bus cable and another ca-
ble in the harness.