The abs and traction actuator turns off the solenoids and the ecm shuts off vsc control (traction control signal) from the skid control ecu accordingly, the result being that it is as if the abs, trc and vsc systems were not installed.
If it is impossible to control the systems, the warning light comes on to inform the driver of malfunctions in the systems (see page bc-44).
Hint:

Freeze frame data
Data list / active testMultiplex communication circuit
Description
The air conditioning amplifier communicates data with the ecm and combination
meter through the can
communication system.
Wiring diagram
Inspection procedure
Check dtc
Clear the dtc (see page ac-127).
Read the dtc (see page ac-127).
Result
Go to can ...
Terminals of ecu
Check tire pressure warning ecu
Disconnect the e56 ecu connector.
Measure the voltage and resistance of the wire
harness side connector.
If the result is not as specified, there may be a
malfunction on the wire harness side.
Reconnect the e56 ecu connector.
Measure the ...
Trailer tongue weight
A recommended tongue weight varies in accordance with the types
of trailers or towing as described below.
To ensure the recommended values shown below, the trailer must
be loaded by referring to the following instructions.
Tongue weight
The gross trailer weight should be distributed so ...