Toyota Tundra. Manual — part 281

28. CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)

a. Disconnect the J2 main body ECU connector.

b. Measure the resistance according to the value(s) in the table below.

Result

RESULT REFERENCE TABLE

Fig. 51: Identifying J2 Main Body ECU And J17 DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO MAIN BODY ECU (NO. 3
JUNCTION CONNECTOR - MAIN BODY ECU)

Tester Connection

Switch Condition Specified Condition Proceed to

J2-16 (CANP) - J2-15 (CANN) Ignition switch OFF

1 ohms or higher

OK

Below 1 ohms

NG

J2-T6 (CANP) - J17-4 (CG)

Ignition switch OFF

1 ohms or higher

OK

J2-15 (CANN) - J17-4 (CG)

J2-16 (CANP) - J17-4 (CG)

Ignition switch OFF

Below 1 ohms

NG

J2-15 (CANN) - J17-4 (CG)

J2-16 (CANP) - J17-16 (BAT)

Ignition switch OFF

1 ohms or higher

OK

J2-15 (CANN) - J17-16 (BAT)

J2-16 (CANP) - J17-16 (BAT)

Ignition switch OFF

Below 1 ohms

NG

J2-15 (CANN) - J17-16 (BAT)

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra

OK: REPLACE MAIN BODY ECU

29. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY

GROUND)

a. Reconnect the cable to the negative (-) battery terminal before measuring the resistances of the

main wire and the branch wire.

b. Disconnect the DA, DB and DD main body ECU connectors.

Fig. 52: Identifying DA, DB And DD Main Body ECU Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

c. Measure the resistance according to the value(s) in the table below.

Standard resistance

STANDARD RESISTANCE SPECIFICATION TABLE

d. Measure the voltage according to the value(s) in the table below.

Standard voltage

STANDARD VOLTAGE SPECIFICATION TABLE

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE MAIN BODY ECU

DTC U1115: LOST COMMUNICATION WITH TILT AND TELESCOPIC MODULE

Tester Connection

Condition Specified Condition

DD-62 (GND1) - Body ground Always

Below 1 ohms

Tester Connection

Condition Specified Condition

DA-1 (ALTB) - Body ground

Always

11 to 14 V

DB-13 (BECU) - Body ground

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra

DESCRIPTION

DTC DETECTION CONDITION AND TROUBLE AREA

WIRING DIAGRAM

Fig. 53: Identifying Lost Communication With Tilt And Telescopic Module - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

a. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the

main wire and the branch wire.

DTC

Code

DTC Detection Condition

Trouble Area

U1115

No communication from multiplex tilt and
telescopic ECU



Power source circuit of multiplex tilt and
telescopic ECU



Multiplex tilt and telescopic ECU



Multiplex tilt and telescopic ECU branch
wire or connector

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra

2. CHECK FOR OPEN IN CAN BUS WIRE (MULTIPLEX TILT AND TELESCOPIC ECU

BRANCH WIRE)

a. Disconnect the J47 multiplex tilt and telescopic ECU connector.

b. Measure the resistance according to the value(s) in the table below.

Standard resistance

STANDARD RESISTANCE SPECIFICATION TABLE

Fig. 54: Identifying J47 Multiplex Tilt And Telescopic ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE MULTIPLEX TILT AND TELESCOPIC ECU BRANCH WIRE OR
CONNECTOR (CANH, CANL)

OK: Go to Next Step

3. CHECK HARNESS AND CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU -

BATTERY AND BODY GROUND)

CAUTION: Wait at least 90 seconds after disconnecting the cable from the

negative (-) battery terminal to prevent airbag and seat belt
pretensioner activation.

NOTE:

After the ignition switch is turned OFF, the navigation system
requires approximately 90 seconds to record various types of
memory and settings. As a result, after turning the ignition switch
OFF, wait 90 seconds or more before disconnecting the cable from
the negative (-) battery terminal.

Tester Connection

Switch Condition Specified Condition

J47-5 (CANH) - J47-14 (CANL) Ignition switch OFF

54 to 69 ohms

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra