Toyota Tundra. Manual — part 1137

CHECK MODE PROCEDURE

HINT:

Compared to the normal mode, check mode is more sensitive to malfunctions. Therefore, check mode can
detect the malfunctions that cannot be detected in normal mode.

1. CHECK MODE PROCEDURE

a. Check and ensure the following condition:

1. Battery positive voltage 11 V or higher.

2. Throttle valve fully closed.

3. Transmission in the P or N position.

4. A/C switch OFF.

b. Turn the ignition switch OFF.

c. Connect the Techstream to the DLC3.

d. Turn the ignition switch ON.

e. Turn the Techstream ON.

f. Enter the following menus: Powertrain/Engine and ECT/Utility/Check Mode.

g. Switch the ECM from normal mode to check mode.

h. Make sure the MIL flashes as shown in the illustration.

i. Start the engine.

j. Make sure the MIL turns OFF.

k. Simulate the conditions of the malfunction described by the customer.

l. Check DTCs and freeze frame data using the Techstream.

DTC Cleared cleared

-

Warmup Cycle

Cleard DTC

Warm-up cycle after DTC
cleared

-

NOTE:

All the stored DTCs and freeze frame data are erased if: 1) the ECM is changed
from normal mode to check mode or vice versa; or 2) the ignition switch is
turned from ON to ACC or OFF while in check mode. Before changing modes,
always check and note any DTCs and freeze frame data.

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

Fig. 33: MIL Blinking Pattern

FAIL-SAFE CHART

If any of the following DTCs are set, the ECM enters fail-safe mode to allow the vehicle to be driven
temporarily.

FAIL-SAFE CHART

DTCs

Components

Fail-Safe Operations

Fail-Safe

Deactivation

Conditions

P0031, P0032, P0051
and P0052

Air-Fuel Ratio
(A/F) Sensor
Heater

ECM turns off A/F sensor heater.

Ignition switch
OFF

P0037, P0038, P0057
and P0058

Heated Oxygen
(HO2) Sensor
Heater

ECM turns off HO2 sensor heater.

Ignition switch
OFF

P0102, P0103

Mass Air Flow
(MAF) Meter

ECM calculates ignition timing according
to engine speed and throttle valve position.

Pass condition
detected

P0110, P0112 and
P0113

Intake Air
Temperature (IAT)
Sensor

ECM estimates IAT to be 20°C (68°F).

Pass condition
detected

P0115, P0117 and
P0118

Engine Coolant
Temperature
(ECT) Sensor

ECM estimates ECT to be 80°C (176°F).

Pass condition
detected

P0120, P0121, P0122,
P0123, P0220, P0222,
P0223, P0604, P0606,
P0607, P060A, P060B,
P060D, P060E, P0657,
P1607, P2102, P2103,
P2111, P2112, P2118,
P2119 and P2135

Electronic Throttle
Control System
(ETCS)

ECM cuts off throttle actuator current and
throttle valve returned to 6° throttle
position by return spring.
ECM then adjusts engine output by
controlling fuel injection (intermittent fuel-
cut) and ignition timing in accordance with
accelerator pedal opening angle, to allow
vehicle to continue at minimal speed.*1

Pass condition
detected and then
ignition switch
turned OFF

P0300, P0301, P0302,
P0303, P0304, P0305
and P0306*2



Fuel injector



Electronic
Throttle
Control
System
(ETCS)

When misfire occurs, fuel cut is performed
for catalyst overheat malfunction
prevention



During normal load and normal
engine speed (MIL is blinking)



Fuel cut is performed on
malfunctioning cylinder



During high load and high engine
speed (MIL is blinking)



Throttle valve opening angle
control is performed

Pass condition
detected and then
ignition switch
turned OFF

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

DATA LIST/ACTIVE TEST

1. DATA LIST

HINT:

Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and
other items to be read without removing any parts. This non-intrusive inspection can be very useful
because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading
the Data List information early in troubleshooting is one way to save diagnostic time

a. Warm up the engine.

b. Turn the ignition switch OFF.

c. Connect the Techstream to the DLC3.

d. Turn the ignition switch ON.

e. Turn the Techstream ON.

f. Enter the following menus: Powertrain/Engine and ECT/Data List.



All cylinder fuel cut or
malfunction cylinder fuel cut

P0327, P0328, P0332
and P0333

Knock Sensor

ECM sets ignition timing to maximum
retard.

Ignition switch
OFF

P0351 to P0356

Igniter

ECM cuts fuel.

Pass condition
detected

P2120, P2121, P2122,
P2123, P2125, P2127,
P2128 and P2138

Accelerator Pedal
Position (APP)
Sensor

APP sensor has 2 sensor circuits: Main and
Sub.
If either of circuits malfunctions, ECM
controls engine using other circuit.
If both of circuits malfunction, ECM
regards accelerator pedal as being released.
As a result, throttle valve is closed and
engine idles.

Pass condition
detected and then
ignition switch
turned OFF

P2432, P2433, P2437,
P2438, P2440, P2442,
P2445, P2447

Air Injection
System

Throttle valve opening angle control is
performed

Pass condition
detected

HINT:



*1: The vehicle can be driven slowly when the accelerator pedal is depressed firmly and slowly. If
the accelerator pedal is depressed quickly, the vehicle may speed up and slow down erratically.



*2: Misfire related fail-safe operations occur when catalyst overheat malfunctions occur.

NOTE:

In the table below, the values listed under Normal Condition are reference
only. Do not depend solely on these values when determining whether or
not a part is faulty.

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra

g. Check the values by referring to the table below.

DATA LIST

Tester

Display

Measurement

Item/Range

Normal Condition*3

Diagnostic Note

Injector (Port)

Injection period of
No. 1 cylinder:
Min.: 0 ms. Max.:
32.64 ms

1.6 to 2.4 msec: Idling

-

IGN Advance

Ignition timing
advance for No. 1
cylinder:
Min.: -64 deg.,
Max.: 63.5 deg.
BTDC 7 to 24°:

Idling

-

Calculate
Load

Calculated load by
ECM:
Min.: 0%, Max.:
100%



11.4 to 16.4%:
Idling



13.1 to 18.9%:
Running without
load (2000
RPM)

-

Vehicle Load

Vehicle load:
Min.: 0%, Max.:
25700%

Actual vehicle load

Load percentage in terms of maximum
intake air flow amount

MAF

Air flow rate from
MAF meter:
Min.: 0 g/sec,
Max.: 655.35
g/sec.

3.2 to 4.7 g/sec: Idling
13.1 to 18.9 g/sec:
2000 RPM

If value approximately 0.0 g/sec:



Mass air flow meter power source
circuit open



VG circuit open or short

If value 160.0 g/sec. or more:



E2G circuit open

Engine Speed

Engine speed:
Min.: 0 RPM,
Max.: 16383.75
RPM

650 to 750 RPM:
Idling

-

Vehicle Speed

Vehicle speed:
Min.: 0 km/h,
Max.: 255 km/h

Actual vehicle speed

Speed indicated on speedometer

Coolant Temp

Engine coolant
temperature:
Min.: -40°C,
Max.: 140°C

80 to 100°C (176 to
212°F):
After warming up



If value -40°C (-40°F): sensor
circuit open



If value 140°C (284°F): sensor
circuit shorted

2008 Toyota Tundra

2008 ENGINE PERFORMANCE Engine Control System (1GR-FE) - Tundra