Toyota Sequoia (2005). Manual - part 317

DIDHZ–01

F19815

: CAN Main Bus Line
  (CAN–H)

DLC3

120 

Ω

±

 10%

Suspension
Control ECU

ECM

: CAN Main Bus Line
  (CAN–L)

: CAN Sub Bus Line
  (CAN–H)

: CAN Sub Bus Line
  (CAN–L)

120 

Ω

±

 10%

Serial Communication Line

Translate ECU

*1: w/ Air Suspension System

*1

*1

Junction
Connector

–

DIAGNOSTICS

CAN COMMUNICATION SYSTEM

DI–1063

1257

SYSTEM DIAGRAM

HINT:

The ECM uses the CAN communication system to perform DTC communication instead of the conven-
tional serial communication line (SIL).

The translate ECU outputs DTCs only via the BRAKE warning light. Therefore, the DTCs cannot be
checked on the hand–held tester display via the CAN VIM.

DIDI0–01

DI–1064

–

DIAGNOSTICS

CAN COMMUNICATION SYSTEM

1258

SYSTEM DESCRIPTION

1.

BRIEF DESCRIPTION

(a)

The CAN (Controller Area Network) is a serial data communication system for real time application.
It is an in–vehicle multiplex communication system that has a high communication speed (500 kbps)
and the function to detect malfunctions.

(b)

By pairing the CANH and CANL bus lines, the CAN performs communication based on differential volt-
age.

(c)

Many ECUs (sensors) installed in the vehicle operate by sharing information and communicating with
each other.

(d)

The CAN has two resistors of 120 

Ω

 which are necessary to communicate with the main bus line.

2.

DEFINITION OF TERMS

(a)

Main bus line
(1)

The main bus line is a wire harness between the two terminus circuits on the bus (communication
line). This is the main bus in the CAN communication system.

(b)

Sub bus line
(1)

The sub bus line is a wire harness that diverges from the main bus line to the ECU.

3.

ECUs THAT COMMUNICATE THROUGH CAN COMMUNICATION SYSTEM

(a)

Translate ECU

(b)

Suspension Control ECU

(c)

ECM

4.

DIAGNOSTIC CODE FOR CAN COMMUNICATION SYSTEM

DTCs for the CAN communication system are as follows:
U0100/65, U0122/67, U0132/72, 65, 94.
HINT:
If C1201/51, C1202/52 or C1203/53 is output from skid control ECU, perform troubleshooting of each diag-
nosis code (see page 

DI–921

).

5.

REMARK FOR TROUBLESHOOTING

(a)

Trouble in the CAN bus (communication line) can be checked from the DLC3 (except when there is
a wire break in lines other than the sub bus line of the DLC3).

NOTICE:
Do not insert the tester directly into the DLC3 connector. Be sure to use a service wire.
(b)

The CAN communication system cannot detect trouble in the sub bus line of the DLC3 even though
the DLC3 is also connected to the CAN communication system.

6.

HOW TO DISTINGUISH THE CAN J/C CONNECTOR

In the CAN communication system, all connectors connected to the CAN J/C are the same shape. The con-
nectors connected to the CAN J/C can be distinguished by the colors of the bus lines.
HINT:
See ”TERMINALS OF ECU” (see page 

DI–1068

) for bus line colors.

DIDI1–01

END

P. 

DI–911

, 

DI–723

Confirmation Test

Items inside          are titles of pages in this manual,
with the page number in the bottom portion. See the
pages listed for detailed explanations.

DTC Combination Table

Vehicle Brought to Workshop

Check and Clear DTCs

P. 

DI–1067

All ECUs connected to the CAN communication system are displayed

An ECU not connected to the CAN communication system is displayed

A few ECUs not connected to the CAN communication system are displayed

Check Using Hand–held Tester via CAN VIM

Select ”BUS CHECK” (see page 

DI–1073

)

P. 

DI–1076

Check CAN Bus Line

Result

Perform troubleshooting in accordance with the procedures on the following page.

A

B

C

Check for an open in one side of the CAN sub–bus line

P. 

DI–1114

P. 

DI–1067

Communication Stop Mode Table

A

B

C

Identification of 
Problem

Repair or Replace

END

Confirmation Test

P. 

DI–1086

, 

DI–1092

, 

DI–1100

, 

DI–1107

Circuit Inspection

Identification of 
Problem

OK

NG

P. 

DI–1079

, 

DI–1081

, 

DI–1083

Circuit Inspection

Repair or Replace

–

DIAGNOSTICS

CAN COMMUNICATION SYSTEM

DI–1065

1259

HOW TO PROCEED WITH TROUBLESHOOTING

NOTICE:

DTCs for the CAN communication system are as follows:
U0100/65, U0122/67, U0132/72, 65, 94.

Refer to troubleshooting of each system if DTCs regarding the CAN communication system are
not output.

DIDI2–01

Inspector’s

Name

:

Customer’s Name

Odometer Reading

/              /

/              /

Frequency Problem Occurs

/                            /

Continuous

Intermittent (       times a day)

km

miles

CAN Communication System Check Sheet

Production Date

VIN

Licence Plate No.

DTC Check

1st Time

2nd Time

Normal System Code

Trouble Code (Code                            )

Normal System Code

Trouble Code (Code                            )

DI–1066

–

DIAGNOSTICS

CAN COMMUNICATION SYSTEM

1260

CUSTOMER PROBLEM ANALYSIS CHECK