Toyota Tundra. Manual — part 1398

Fig. 186: Identifying EFI No. 1 Fuse

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.

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

Standard resistance

STANDARD RESISTANCE SPECIFICATION

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.

Standard resistance

STANDARD RESISTANCE SPECIFICATION

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

Tester Connection

Condition

Specified

2008 Toyota Tundra

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

Fig. 187: Identifying A24 ECM Connector & EFI No. 1 Fuse

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

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

2008 Toyota Tundra

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

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 OR REPLACE 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.

Result

RESULT REFERENCE

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 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 set a DTC immediately.

DTC DETECTION CONDITION AND TROUBLE AREA

Result

Proceed To

P0560 is output

A

No DTC is output

B

2008 Toyota Tundra

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

MONITOR STRATEGY

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

TYPICAL MALFUNCTION THRESHOLDS

INSPECTION PROCEDURE

1. CHECK DTC

a. Clear DTC. (See DTC CHECK/CLEAR ).

b. Turn the ignition switch off.

c. Disconnect the cable from the negative battery terminal and wait for 1 minute.

d. Connect the cable to the negative (-) battery terminal.

e. Turn the ignition switch to ON.

f. Check DTC.

OK: P0604 is not present.

NG : REPLACE ECM (See REMOVAL )

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

DTC P0606 ECM/PCM PROCESSOR

DESCRIPTION

DTC Code

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

None

-

Main CPU and sub CPU mirroring

Fail

2008 Toyota Tundra

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