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HOMESERVICE MANUALSTOYOTA2009SEQUOIA LIMITED, 5.7 Y, RWDREPAIR AND DIAGNOSISACCESSORIES & EQUIPMENTCOMMUNICATION DEVICESNETWORKINGCAN COMMUNICATION SYSTEMDIAGNOSIS SYSTEM

2009 Toyota Sequoia Limited, 5.7 Y, RWD

Diagnosis System

2009 Toyota Sequoia Limited, 5.7 Y, RWDSECTION Diagnosis System

BUS CHECK
1. Select "CAN Bus Check" from the "System Select "screen on the Techstream.
  HINT:
  - If any properly connected ECUs or sensors are not displayed, there is a communication stop in the system (See PROBLEM SYMPTOMS TABLE ).
  - Display the communication BUS check screen for approximately 1 minute and check for ECUs and sensors that are not indicated on the screen.

CHECK INSTALLED SYSTEMS (ECUs AND SENSORS) THAT ADOPT CAN COMMUNICATION

Systems (ECUs and sensors) that adopt CAN communication vary depending on the vehicle optional settings. Check which systems (ECUs and sensors) are installed on the vehicle.

VEHICLE OPTIONAL SETTINGS CHART

ECU/Sensor Name	Installed to
Power steering ECU	All vehicles
Skid control ECU	All vehicles
Air conditioning amplifier	All vehicles
ECM	All vehicles
Main body ECU	All vehicles
Combination meter ECU	All vehicles
Center airbag sensor assembly	All vehicles
Steering angle sensor	All vehicles
Bus buffer ECU	Vehicles with bus buffer ECU (w/ Bus buffer ECU)
4WD control ECU	Vehicles with 4 wheel drive (w/ 4WD)
Power seat control ECU	Vehicles with front power seat control system (w/ Seat memory)
Outer mirror control ECU	Vehicles with front power seat control system (w/ Seat memory)
Multiplex tilt and telescopic ECU	Vehicles with front power seat control system (w/ Seat memory)
Air suspension ECU	Vehicles with air suspension system
Distance control ECU	Vehicles with dynamic laser cruise control system
Power back door ECU	Vehicles with power back door system

DTC TABLE BY ECU

HINT:

In the CAN communication system, CAN communication system DTCs output by the ECU can be displayed by using the Techstream.
If CAN communication system DTCs are output, the trouble cannot be determined solely from the DTCs. Perform troubleshooting according to "HOW TO PROCEED WITH TROUBLESHOOTING " .

MULTIPLEX TILT AND TELESCOPIC ECU

HINT:

DTC communication uses the CAN communication system.

DTC DETECTION REFERENCE CHART

DTC No.	Detection Item
B2621	Communication Interruption

MAIN BODY ECU

HINT:

DTC communication uses the CAN communication system.

DTC DETECTION REFERENCE CHART

DTC No.	Detection Item
U1002	Lost Communication with Gateway Module
U0199	Lost Communication with "Door Control Module A"
U0208	Lost Communication with "Seat Control Module A"
U1115	Lost Communication with Tilt and Telescopic Module
U0230	Lost Communication with Rear Gate Module

ECM

HINT:

DTC communication uses the CAN communication system.
Distance control ECU data is also output.

DTC DETECTION REFERENCE CHART

DTC No.

Detection Item

U0100 (⁽³⁾)

Lost Communication with ECM/PCM "A"

U0101 (⁽¹⁾)

Lost Communication With Transfer Case Control Module

U0122 (⁽³⁾)

Lost Communication with Vehicle Dynamics Control Module

U0123 (⁽²⁾)

Lost Communication with Yaw Rate Sensor Module

U0126 (⁽³⁾)

Lost Communication with Steering Angle Sensor Module

U0235 (⁽²⁾)

Lost Communication with Cruise Control Front Distance Range Sensor

U1101 (⁽³⁾)

Lost Communication with Distance Control ECU

U1102 (⁽²⁾)

Lost Communication with Radar Sensor

⁽¹⁾	For vehicle with 2UZ-FE only. The ECM is malfunctioning if U0101 is output. Replace the ECM.

⁽²⁾	If U0123, U0235 or U1102 is output alone, the CAN bus is normal (See DTC U0123 COMMUNICATION ERROR OF YAW RATE SENSOR for U0123, See DTC U0235 LOST COMMUNICATION WITH CRUISE CONTROL FRONT DISTANCE RANGE SENSOR; DTC U1102 LOST COMMUNICATION WITH RADAR SENSOR for U0235 and U1102).

⁽³⁾	Dynamic laser cruise DTC.

SKID CONTROL ECU

HINT:

DTC communication uses the CAN communication system.

DTC DETECTION REFERENCE CHART

DTC No.	Detection Item
U0073	Control Module Communication Bus OFF
U0100	Lost Communication with ECM/PCM "A"
U0114	Lost Communication with 4-Wheel Drive Clutch Control Module
U0123	Lost Communication with Yaw Rate Sensor Module
U0124	Deceleration Sensor Communication Circuit Malfunction
U0126	Lost Communication with Steering Angle Sensor Module

COMBINATION METER ECU

HINT:

DTC communication uses the CAN communication system.

DTC DETECTION REFERENCE CHART

DTC No.	Detection Item
U0100	Lost Communication with ECM/PCM "A"
U0129	Lost Communication with Brake System Control Module

AIR CONDITIONING AMPLIFIER

HINT:

DTC communication uses the CAN communication system.

DTC DETECTION REFERENCE CHART

DTC No.	Detection Item
B1499	Multiplex Communication Circuit

SUSPENSION CONTROL ECU

For Vehicle with air suspension system only.

HINT:

DTC communication uses the CAN communication system.

DTC DETECTION REFERENCE CHART

DTC No.	Detection Item
U0100	Lost Communication with ECM/PCM "A"
U0122	Lost Communication with Vehicle Dynamics Control Module
U0126	Lost Communication with Steering Angle Sensor Module

STEERING ANGLE SENSOR
HINT:

The steering angle sensor is connected to the CAN communication system but CAN communication DTCs are not output.
CENTER AIRBAG SENSOR
HINT:

The center airbag sensor is connected to the CAN communication system but CAN communication DTCs are not output.
POWER STEERING ECU
HINT:

The power steering ECU is connected to the CAN communication system but CAN communication DTCs are not output.
POWER BACK DOOR ECU
For vehicle with power back door system only.

HINT:

The power back door ECU is connected to the CAN communication system but CAN communication DTCs are not output.
4WD CONTROL ECU
For vehicle with 4 wheel drive only.

HINT:

The 4WD control ECU is connected to the CAN communication system but CAN communication DTCs are not output.
DISTANCE CONTROL ECU
For Vehicle with dynamic laser cruise control system only.

HINT:

The distance control ECU is connected to the CAN communication system but CAN communication DTCs are not output.
BUS BUFFER ECU
For vehicle with bus buffer ECU only.

HINT:

The bus buffer ECU is connected to the CAN communication system but CAN communication DTCs are not output.
POWER SEAT CONTROL ECU
For vehicle with front power seat control system (w/ Seat memory) only.

HINT:

The power seat control ECU is connected to the CAN communication system but CAN communication DTCs are not output.
OUTER MIRROR CONTROL ECU
For vehicle with front power seat control system (w/ Seat memory) only.

HINT:

The outer mirror control ECU is connected to the CAN communication system but CAN communication DTCs are not output.

DTC COMBINATION TABLE

V Bus

DTC COMBINATION REFERENCE CHART - V BUS

Output from	Output DTC	Detection Item	Trouble Mode
Output from	Output DTC	Detection Item	Main Body ECU Communication Stop Mode	ECM Communication Stop Mode	Skid Control ECU Communication Stop Mode	Steering Angle Sensor Communication Stop Mode	Combination Meter ECU Communication Stop Mode	Center Airbag Sensor Communication Stop Mode
Skid Control ECU	U0073	Control Module Communication Ω Bus OFF	□	□	□	□	□	□
	U0100	Lost Communication with ECM/ PCM "A"	-	-	◦	-	-	-
	U0114	Lost Communication with 4-Wheel Drive Clutch Control Module	-	-	◦	-	-	-
	U0123	Lost Communication with Yaw Rate Sensor Module	-	-	-	-	-	-
	U0124	Deceleration Sensor Communication Circuit Malfunction	-	-	-	-	-	-
	U0126	Lost Communication with Steering Angle Sensor Module	-	-	◦	◦	-	-
Combination Meter ECU	U0100	Lost Communication with ECM/ PCM "A"	-	◦	-	-	◦	-
Combination Meter ECU	U0129	Lost Communication with Brake System Control Module	-	-	◦	-	◦	-
Air Conditioning Amplifier	B1499*1	Multiplex Communication Circuit	-	◦	-	-	-	-
Suspension Control ECU	U0100*1	Lost Communication with ECM/ PCM "A"	-	◦	-	-	-	-
	U0122*1	Lost Communication with Vehicle Dynamics Control Module	-	-	◦	-	-	-
	U0126*1	Lost Communication with Steering Angle Sensor Module	-	-	-	◦	-	-
ECM	U0100*2	Lost Communication with ECM/ PCM "A"	-	◦	-	-	-	-
	U1101*2	Lost Communication with Distance Control ECU	-	◦	-	-	-	-
	U0122*2	Lost Communication with Vehicle Dynamic Control Module	-	◦	◦	-	-	-
	U0123*2	Lost Communication with Yaw Rate Sensor Module	-	◦	-	-	-	-
	U0126*2	Lost Communication with Steering Angle Sensor Module	-	◦	-	◦	-	-
HINT: ◦: DTC is stored. □: Communication error status is stored. (e.g., 1 wire disconnection) 1: Only during failure status. 2: Only during ignition switch ACC.

V Bus

DTC COMBINATION REFERENCE CHART - V BUS

Output from	Output DTC	Detection Item	Trouble Mode
Output from	Output DTC	Detection Item	Air Conditioning Amplifier Communication Stop Mode	4WD Control ECU Communication Stop Mode	Suspension Control ECU Communication Stop Mode	Power Steering ECU Communication Stop Mode	Distance Control ECU Communication Stop Mode
Skid Control ECU	U0073	Control Module Communication Bus OFF	□	□	□	□	□
	U0100	Lost Communication with ECM/PCM "A"	-	-	-	-	-
	U0114	Lost Communication with 4-Wheel Drive Clutch Control Module	-	◦	-	-	-
	U0123	Lost Communication with Yaw Rate Sensor Module	-	-	-	-	-
	U0124	Deceleration Sensor Communication Circuit Malfunction	-	-	-	-	-
	U0126	Lost Communication with Steering Angle Sensor Module	-	-	-	-	-
Combination Meter ECU	U0100	Lost Communication with ECM/PCM "A"	-	-	-	-	-
Combination Meter ECU	U0129	Lost Communication with Brake System Control Module	-	-	-	-	-
Air Conditioning Amplifier	B1499*1	Multiplex Communication Circuit	◦	-	-	-	-
Suspension Control ECU	U0100*1	Lost Communication with ECM/PCM "A"	-	-	■	-	-
	U0122*1	Lost Communication with Vehicle Dynamics Control Module	-	-	■	-	-
	U0126*1	Lost Communication with Steering Angle Sensor Module	-	-	-	-	-
ECM	U0100*2	Lost Communication with ECM/PCM "A"	-	-	-	-	-
	U1101*2	Lost Communication with Distance Control ECU	-	-	-	-	◦
	U0122*2	Lost Communication with Vehicle Dynamic Control Module	-	-	-	-	-
	U0123*2	Lost Communication with Yaw Rate Sensor Module	-	-	-	-	◦
	U0126*2	Lost Communication with Steering Angle Sensor Module	-	-	-	-	◦
HINT: ◦: DTC is stored. □: Communication error status is stored, (e.g., 1 wire disconnection) ■ : DTC is not stored, but is output. 1: Only during failure status. 2: Only during ignition switch ACC.

MS Bus

DTC COMBINATION REFERENCE CHART - MS BUS

Output from	Output DTC	Detection Item	Trouble Mode
Output from	Output DTC	Detection Item	Power Seat Control ECU Communication Stop Mode	Outer Mirror Control ECU Communication Stop Mode	Multiplex Tilt and Telescopic ECU Communication Stop Mode	Power Back Door ECU Communication Stop Mode	Main Body ECU Communication Stop Mode
Multiplex Tilt and Telescopic ECU	B2621	Communication Interruption	◦	-	◦	◦	◦
Main Body ECU	U1002	Lost Communication with Gateway Module	-	-	-	-	◦
	U0208	Lost Communication with "Seat Control Module A"	◦	-	-	-	◦
	U0199	Lost Communication with "Door Control Module A"	-	◦	-	-	◦
	U1115	Lost Communication with Tilt and Telescopic Module	-	-	◦	-	◦
	U0230	Lost Communication with Rear Gate Module	-	-	-	◦	◦
HINT: ◦: DTC is stored.

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.