Toyota Tundra. Manual — part 303

Fig. 135: Identifying Short To GND In CAN Bus Line - Wiring Diagram (1 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra

Fig. 136: Identifying Short To GND In CAN Bus Line - Wiring Diagram (2 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

HINT:

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with
the CAN, which causes resistance variation.

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.

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

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

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra

2. CHECK FOR SHORT TO GND IN CAN BUS WIRE (DLC3 BRANCH WIRE)

a. Disconnect the J86 No. 1 junction connector connector.

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

Result

RESULT REFERENCE TABLE

Fig. 137: Identifying J17 DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CANH, CANL)

OK: Go to next step

3. CONNECT CONNECTOR

a. Reconnect the J86 No. 1 junction connector connector.

4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR SIDE)

a. Disconnect the J93 No. 2 junction connector connector.

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

Result

RESULT REFERENCE TABLE

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 Measured Resistance Proceed to

J17-6 (CANH) - J17-4 (CG)

Ignition switch OFF

1 ohms or higher

OK

J17-14 (CANL) - J17-4 (CG)

J17-6 (CANH) - J17-4 (CG)

Ignition switch OFF

Below 1 ohms

NG

J17-14 (CANL) - J17-4 (CG)

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra

Fig. 138: Identifying J17 DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: Go to step 17

OK: Go to next step

5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 1 JUNCTION CONNECTOR - NO. 2

JUNCTION CONNECTOR)

a. Disconnect the J94 No. 1 junction connector.

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

Result

RESULT REFERENCE TABLE

Tester Connection

Switch Condition Measured Resistance Proceed to

J17-6 (CANH) - J17-4 (CG)

Ignition switch OFF

1 ohms or higher

OK

J17-14 (CANL) - J17-4 (CG)

J17-6 (CANH) - J17-4 (CG)

Ignition switch OFF

Below 1 ohms

NG

J17-14 (CANL) - J17-4 (CG)

Tester Connection

Switch Condition Measured Resistance Proceed to

J94-1 (CANH) - J17-4 (CG)

Ignition switch OFF

1 ohms or higher

OK

J94-2 (CANL) - J17-4 (CG)

J94-1 (CANH) - J17-4 (CG)

Ignition switch OFF

Below 1 ohms

NG

J94-2 (CANL) - J17-4 (CG)

2009 Toyota Tundra

2009 ACCESSORIES & EQUIPMENT CAN Communication - Tundra