Toyota Tundra. Manual — part 1452

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

OK : Go to Next Step

3. REPLACE FUEL PUMP ECU

a. Replace the fuel pump ECU. (See FUEL PUMP ECU ).

4. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

a. Check the fuel pump operation.

OK: Malfunction has been repaired successfully.

NG : REPLACE ECM (See REMOVAL )

OK : END

5. INSPECT CIRCUIT OPENING RELAY (C/OPN)

a. Remove the circuit opening relay (C/OPN) from the engine room relay block.

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

Standard resistance

STANDARD RESISTANCE SPECIFICATION

Fig. 290: Inspecting Circuit Opening Relay (C/OPN)

NG : REPLACE CIRCUIT OPENING RELAY (C/OPN) (See ON-VEHICLE INSPECTION )

OK : Go to Next Step

6. INSPECT CIRCUIT OPENING RELAY (POWER SOURCE VOLTAGE)

a. Remove the circuit opening relay (C/OPN) from the engine room relay block.

b. Turn the ignition switch to ON.

Standard resistance

Condition

Specified Condition

3 - 5

When no battery voltage applied to terminals 1 and 2 10 kohms or higher

3 - 5

When battery voltage applied to terminals 1 and 2

Below 1 ohms

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra

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

Standard voltage

STANDARD VOLTAGE SPECIFICATION

Fig. 291: Identifying Opening Relay (C/OPN)

NG : Go to step 13

OK : Go to Next Step

7. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - ECM AND

FUEL PUMP ECU)

a. Remove the circuit opening relay (C/OPN) from the engine room relay block.

b. Disconnect the A24 ECM connector.

c. Disconnect the R7 fuel pump ECU connector.

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

Standard resistance

STANDARD RESISTANCE SPECIFICATION

Tester Connection

Switch Condition Specified Condition

C/OPN relay (2) - Body ground Ignition switch ON

11 to 14 V

C/OPN relay (5) - Body ground Ignition switch ON

11 to 14 V

Tester Connection

Condition Specified Condition

C/OPN relay (1) - A24-48 (FC)

Always

Below 1 ohms

C/OPN relay (3) - R7-4 (+B)

Always

Below 1 ohms

C/OPN relay (1) or A24-48 (FC) - Body ground Always

10 kohms or higher

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra

Fig. 292: Identifying A24 ECM & R7 Fuel Pump ECU Connectors

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

C/OPN relay (3) or R7-4 (+B) - Body ground

Always

10 kohms or higher

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra

OK : Go to Next Step

8. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP ECU)

a. Disconnect the R6 fuel pump connector.

b. Disconnect the R8 fuel pump ECU connector.

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

Standard resistance

STANDARD RESISTANCE SPECIFICATION

Fig. 293: Identifying R6 Fuel Pump & R8 Fuel Pump ECU Connectors

NG : REPAIR OR REPLACE HARNESS OR CONNECTOR

Tester Connection

Condition Specified Condition

R6-4 (B2) - R8-1 (FP)

Always

Below 1 ohms

R6-5 (E2) - 8-2 (FP-)

Always

Below 1 ohms

R6-4 (B2) or R8-1 (FP) - Body ground

Always

10 kohms or higher

R6-5 (E2) or R8-2 (FP-) - Body ground Always

10 kohms or higher

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (2UZ-FE) - Tundra