Toyota Tundra. Manual — part 2775

DESCRIPTION

Speed signals are input into the tire pressure warning ECU from the combination meter. At the same time, the
G-SW in the tire pressure warning valve and transmitter detects driving conditions, and sends signals to the tire
pressure warning ECU. If the speed signal from the combination meter stops and the G-SW signal in the tire
pressure warning valve and transmitter indicates that the vehicle is being driven, DTC C2174/74 is stored.

DTC C2191/91 is stored only during the signal check.

DTC DETECTION CONDITION TABLE

WIRING DIAGRAM

Fig. 28: Vehicle Speed Signal Malfunction - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

DTC Code

Detection Condition

Trouble Area

C2174/74 Vehicle speed signal malfunction



Combination meter



Vehicle speed signal circuit



Harness or connector



Tire pressure warning ECU



Tire pressure warning valve and transmitter

C2191/91 Test mode procedure is performed



Meter/gauge system (speed signal)



Vehicle speed signal circuit



Harness or connector



Tire pressure warning ECU

NOTE:



When replacing the tire pressure warning ECU, read the transmitter IDs
stored in the old ECU using the Techstream and write them down before
removal.



It is necessary to perform INITIALIZATION after REGISTRATION of the

2009 Toyota Tundra

2009 SUSPENSION Tire & Wheel - Tundra

HINT:

When the speedometer needle is not moving, first troubleshoot the meter/gauge system (See HOW TO
PROCEED WITH TROUBLESHOOTING ).

1. READ VALUE USING DATA LIST (VEHICLE SPEED)

a. Turn the ignition switch off.

b. Connect the Techstream to the DLC3.

c. Turn the ignition switch to ON and the Techstream on.

d. Enter the following menus: Chassis/Tire Pressure Monitor/Data List.

e. Check that the values indicated on the Techstream and on the combination meter are the same.

Tire Pressure Monitor

TIRE PRESSURE MONITOR TABLE

OK: Vehicle speed indicated on the Techstream indicates the actual speed.

NG: Go to step 3

OK: Go to next step

2. CHECK DTC

a. Perform a driving test.

b. Check for DTCs.

HINT:

The time required for DTC C2174 to be stored is 20 minutes.

Result

RESULT TABLE

transmitter IDs into the tire pressure warning ECU after the ECU and/or tire
pressure warning valve and transmitter has been replaced.

Tester

Display

Measurement

Item/Range

Normal Condition

Diagnostic Note

Vehicle

Speed

Vehicle speed/
min.: 0 km/h (0 mph)
max.: 255 km/h (158
mph)

Almost same as actual
vehicle speed

Speed indicated on
combination meter

Result

Proceed to

DTC C2174 is not output

A

2009 Toyota Tundra

2009 SUSPENSION Tire & Wheel - Tundra

B: Go to step 6

A: USE SIMULATION METHOD TO CHECK (See HOW TO PROCEED WITH
TROUBLESHOOTING )

3. CHECK HARNESS AND CONNECTOR (ECU - COMBINATION METER)

a. Disconnect the J31 tire pressure warning ECU connector.

b. Disconnect the J28 meter connector.

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION TABLE

Fig. 29: Identifying J31 Tire Pressure Warning ECU Connector & J28 Meter Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

DTC C2174 is output

B

Tester Connection

Condition Specified Condition

J31-2 (SPD) - J28-35 (+S)

Always

Below 1 ohms

J31-2 (SPD) - Body ground Always

10 kohms or higher

2009 Toyota Tundra

2009 SUSPENSION Tire & Wheel - Tundra

4. CHECK HARNESS AND CONNECTOR (COMBINATION METER - SKID CONTROL ECU)

Fig. 30: Identifying Combination Meter Connector J28 & Skid Control ECU Connector Terminals
A17
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

a. Disconnect the A17 skid control ECU connector.

b. Disconnect the J28 meter connector.

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

Standard Resistance

TESTER CONNECTION SPECIFIED CONDITION TABLE

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

5. CHECK DTC (SFI SYSTEM)

a. Check for DTCs.

HINT:



for 1GR-FE (See DTC CHECK/CLEAR ).



for 2UZ-FE (See DTC CHECK/CLEAR ).



for 3UR-FE (See DTC CHECK/CLEAR ).

Result

Tester Connection

Condition Specified Condition

A17-14 (SP1) - J28-36 (S1)

Always

Below 1 ohms

A17-14 (SP1) - Body ground Always

10 kohms or higher

2009 Toyota Tundra

2009 SUSPENSION Tire & Wheel - Tundra