Toyota Tacoma (2015-2018) Service Manual: Fail-safe Chart
FAIL-SAFE CHART
1. Fail-safe
This function minimizes the loss of operation when any abnormality occurs in a sensor or solenoid.
Fail-safe Control List|
Malfunction Part |
Function |
|---|---|
|
Transmission revolution sensor (NT) |
During a transmission revolution sensor (NT) malfunction, shift control is performed based on the transmission revolution sensor (SP2) signal. |
|
Transmission revolution sensor (SP2) |
During a transmission revolution sensor (SP2) malfunction, shift control is performed based on the wheel speed sensor signal. |
|
ATF temperature sensors (No. 1 and No. 2) |
During an ATF temperature sensor malfunction, up-shifting to 5th and 6th is prohibited. |
|
Shift solenoid valve SL1, SL2, SL3 and SL4 |
Stop the conduction of electric power to a failed solenoid and shift gears by turning on/off normal solenoids. If all solenoids are malfunctioning, gears will be selected through mechanical hydraulic circuits. |
|
Shift solenoid valve SLT |
During a shift solenoid valve SLT malfunction, the current to the shift solenoid valve is stopped. However, shifting is performed through normal clutch pressure control. |
|
Shift solenoid valve SLU |
During a shift solenoid valve SLU malfunction, the current to the shift solenoid valve is stopped. This stops lock-up control, thus decreasing fuel economy. |
|
Gear Position |
1st |
2nd |
3rd |
4th |
5th |
6th |
|---|---|---|---|---|---|---|
|
Shift solenoid valve SL1 |
ON |
ON |
ON |
ON |
OFF |
OFF |
|
Shift solenoid valve SL2 |
OFF |
OFF |
OFF |
ON |
ON |
ON |
|
Shift solenoid valve SL3 |
OFF |
ON |
OFF |
OFF |
OFF |
ON |
|
Shift solenoid valve SL4 |
OFF |
OFF |
ON |
OFF |
ON |
OFF |
|
Gear Position under Normal Conditions |
1st |
2nd |
3rd |
4th |
5th |
6th |
|
|---|---|---|---|---|---|---|---|
|
Shift solenoid valve SL1 |
ON Malfunction (without Fail-safe Control)* |
1st |
2nd |
3rd |
4th |
4th |
4th |
|
OFF Malfunction (without Fail-safe Control) |
1st to N |
2nd to N |
3rd to N |
4th to N |
5th |
6th |
|
|
Fail-safe Control during OFF Malfunction |
Fixed in 3rd or 5th |
||||||
|
Shift solenoid valve SL2 |
ON Malfunction (without Fail-safe Control)* |
1st to 4th |
2nd to 4th |
3rd to 4th |
4th |
5th |
6th |
|
OFF Malfunction (without Fail-safe Control) |
1st |
2nd |
3rd |
4th to 1st |
5th to N |
6th to N |
|
|
Fail-safe Control during OFF Malfunction |
Fixed in 2nd or 3rd |
||||||
|
Shift solenoid valve SL3 |
ON Malfunction (without Fail-safe Control)* |
1st to 2nd |
2nd |
3rd |
4th |
5th |
6th |
|
OFF Malfunction (without Fail-safe Control) |
1st |
2nd to 1st |
3rd |
4th |
5th |
6th to N |
|
|
Fail-safe Control during OFF Malfunction |
Fixed in 3rd |
||||||
|
Shift solenoid valve SL4 |
ON Malfunction (without Fail-safe Control)* |
3rd |
3rd |
3rd |
4th |
5th |
5th |
|
OFF Malfunction (without Fail-safe Control) |
1st |
2nd |
3rd to 1st |
4th |
5th to N |
6th |
|
|
Fail-safe Control during OFF Malfunction |
Fixed in 2nd |
||||||
- *: Fail-safe control is not actuated when an ON malfunction occurs.
Data List / Active Test
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 p ...
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART
If a DTC is displayed during the DTC check, check the parts listed in
the table below and proceed to the "See page" given.
*1: "Comes on&qu ...
Other materials:
Power Source Mode does not Change to ON (ACC)
DESCRIPTION
If the engine switch is pressed with the electrical key transmitter sub-assembly
in the cabin, the certification ECU (smart key ECU assembly) receives a signal and
changes the power source mode.
HINT:
When the cable is disconnected and reconnected to the negative (-) battery termi ...
Brake System Malfunction (C1A50)
DESCRIPTION
When the pre-collision system is operating, the millimeter wave radar sensor
assembly sends brake control signals to the skid control ECU (master cylinder solenoid)*1
or skid control ECU (brake actuator assembly)*2.
If the millimeter wave radar sensor assembly receives a vehicle st ...
Check Bus 3 Lines for Short Circuit
DESCRIPTION
There may be a short circuit between the CAN main bus lines and/or CAN branch
lines when the resistance between terminals 6 (CA3H) and 21 (CA3L) of the central
gateway ECU (network gateway ECU) is below 54 Ω.
Detection Item
Trouble Area
Resis ...
