Toyota Tundra. Manual — part 1585

Fig. 198: System Voltage - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

HINT:

Read freeze frame data using the Techstream Freeze frame data records the engine condition when
malfunctions are detected When troubleshooting, freeze frame data can help determine if the vehicle was
moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data
from the time the malfunction occurred

1

INSPECT FUSE (EFI NO. 1)

a

Remove the EFI NO 1 fuse from the engine room relay block

Fig. 199: Identifying EFI NO. 1 Fuse On Engine Room Relay Block
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2009 Toyota Tundra

2009 ENG NE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

b

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

Standard resistance

RESISTANCE SPECIFIED CONDITIONS

NG: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED
TO FUSE AND REPLACE FUSE

OK: Go to Next Step

2

CHECK HARNESS AND CONNECTOR (EFI NO. 1 FUSE - ECM, BATTERY)

a

Check the harness and the connector between the EFI NO 1 fuse and ECM

1

Remove the EFI NO 1 fuse from the engine room relay block

2

Disconnect the A24 ECM connector

Fig. 200: Identifying EFI No. 1 Fuse And A24 ECM Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

3

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

Standard resistance

RESISTANCE SPECIFIED CONDITIONS

b

Check the harness and the connector between the EFI NO 1 fuse and battery

1

Remove the EFI NO 1 fuse from the engine room relay block

2

Disconnect the positive battery terminal

3

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

Tester Connection Condition Specified Condition

EFI NO 1 fuse

Always

Below 1 ohms

Tester Connection

Condition Specified Condition

EFI NO 1 fuse terminal 2 - A24-1 (BATT)

Always

Below 1 ohms

EFI NO 1 fuse terminal 2 or A24-1 (BATT) - Body ground Always

10 kohms or higher

2009 Toyota Tundra

2009 ENG NE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

Standard resistance

RESISTANCE SPECIFIED CONDITIONS

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to Next Step

3

INSPECT BATTERY

a

Check that the battery is not depleted (see ON-VEHICLE INSPECTION )

OK:

Battery is not depleted.

NG: REPLACE BATTERY

OK: Go to Next Step

4

CHECK BATTERY TERMINAL

a

Check that the battery terminals are not loose or corroded

OK:

Battery terminals are not loose or corroded.

NG: REPAIR BATTERY TERMINAL

OK: Go to Next Step

5

CHECK WHETHER DTC OUTPUT RECURS

a

Connect the Techstream to the DLC3

b

Turn the ignition switch to ON and turn the Techstream ON

c

Clear DTCs (see DTC CHECK/CLEAR )

d

Turn the ignition switch off and turn the Techstream OFF

e

Start the engine and turn the Techstream ON

f

Enter the following menus: Powertrain/Engine and ECT/Trouble Codes

g

Read DTCs

Tester Connection

Condition

Specified

Condition

Battery positive (+) terminal - EFI NO 1 fuse terminal 1

Always

Below 1 ohms

Battery positive (+) terminal or EFI NO 1 fuse terminal 1 -
Body ground

Always

10 kohms or

higher

2009 Toyota Tundra

2009 ENG NE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

Result

DTC OUTPUT RESULT

B: CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT
PROBLEMS )

A: REPLACE ECM (See REMOVAL )

DTC P0604 RANDOM ACCESS MEMORY (RAM)

DESCRIPTION

The ECM continuously monitors its internal memory status This self-check ensures that the ECM is
functioning properly This is diagnosed by internal "mirroring" of the main CPU and sub CPU to detect the
Random Access Memory (RAM) errors If outputs from these CPUs are different and deviate from the standard,
the ECM will illuminate the MIL and store a DTC immediately

DTC DETECTION CONDITION AND TROUBLE AREA REFERENCE CHART

MONITOR STRATEGY

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

TYPICAL MALFUNCTION THRESHOLDS CONDITIONS

Result

Proceed to

P0560 is output

A

No DTC is output

B

DTC

DTC Detection Condition

Trouble Area

P0604

ECM RAM errors

ECM

Related DTCs

None

Required sensors/components (main)

ECM

Required sensors/components (sub)

None

Frequency of operation

Continuous

Duration

16 seconds

MIL operation

Immediate

Sequence of operation

None

Monitor runs whenever following DTCs not present

None

Main CPU and sub CPU mirroring

Fail

2009 Toyota Tundra

2009 ENG NE PERFORMANCE Engine Control System (3UR-FBE) - Tundra