Mitsubishi MOTORS Outlander 2007, Service Manual, Technical Information & Body Repair Manual Data

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the 3.5 volts state and CAN_L is under the 1.5 volts
state. On the other hand, the voltage transformation
(output signal) when the data frame is sent to the
CAN-B bus line has a distinctive CAN-B profile. The
transmitting ECU through the CAN_H and CAN_L bus
lines sends 0 to 4 volts signals to the CAN_H side, and
1 to 5 volts signals to the CAN_L side. "Recessive" is
a state in which CAN_H is at 0 volt and CAN_L is at 5
volts, and "Dominant" is a state in which CAN_H is at 4 volts and CAN_L is at 1 volt. By transformation
mainly to 2.5 volts, even in cases when voltage is
rendered 0 from faulty grounding or the like (causing
a problem of an approximate 0.5 volt increase on the
communications line), communication can be
continued
uninterrupted. Employing dual
communications lines improves reliability to prevent
the presence of noise, compared to the conventional
communication method.
DATA FRAMES
ZC5017700000
SOF EOF
ID
region
CRC
region
ACK
region
Control
region
Data region
Data frames
51(5VCTVQH(TCOG
Indicates the start of the frame
+&+FGPVKHKGTTGIKQP
Identifies the data content while specifying priority
rank in case of mediation
%QPVTQNTGIKQP
Specifies the frame type, data length, etc.
&CVCTGIKQP
Values used for data control, etc.
%[ENKE4GFWPFCPE[%JGEM%4%TGIKQP
Region where to check for errors in sent data. The
transmitting ECU calculates data regions by
applying prescribed operations and stores the
results. The receiving ECU detects erroneous
communication by comparing the CRC region with
the data region.
#%-#EMPQYNGFIGTGIKQP
Region where to conform the reception of sent data
'1('PFQH(TCOG
Indicates the end of the frame
ERROR DETECTION AND RECOVERY
CAN protocol secures its reliability of communication
by providing several error detection function such as
CRC shown in data frame, and the recovery function
(recovery is performed by resending, from abnormal
state such as transmission errors). If an error is
detected but it is not resolved even after recovery,
communication is stopped. This state is called "Bus
Off."
SELF-DIAGNOSIS
M25402000004USA0000010000
CAN self-diagnosis is performed by each ECU
connected to the CAN bus.
Diagnosis codes related to communication are
named with the capital letter U, and are called "U-
codes."
A summary of the CAN self-diagnosis system is
presented below. For further details on each
diagnostic trouble code stored by the ECUs.
TIME-OUT
Each ECU transmits data frames periodically. If the
data frame is not received within the specified period,
the intended receiving ECU transmits a diagnostic
trouble code indicating communication time-out for
the ECU that failed to transmit.
&
%10641..'4#4'#0'6914-%#0
5'.(&+#)015+5