Volvo TSI, Manual

Page: 46 / 250

Group 28 Design and Function
SAE J1939 Control Data Link
The system’s control signals are sent via this link.
The J1939 link is very fast, operating at 250,000 bits per
second. This operating speed allows the system to func-
tion more effectively and adapt quickly to changing
conditions and vehicle requirements.
The link complies with SAE standards, and consists of
three twisted wires: a green wire (407), a yellow wire
(406) and in early deisgns a shield wire (408–optional).
The twisted wire set (40 turns per meter) is used to pro-
tect the link from electrical interference.
CAUTION
No modifications or connections should be made to
wires 406 (yellow), 407 (green) or 408 (shielded).
These wires carry the high-speed communications be-
tween the electronic systems in the vehicle. Any
modification, connection to, or damage to these
wires can result in the failure of the vehicle’s elec-
tronic systems.
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