Toyota Tacoma (2015-2018) Service Manual: Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
The 4 wheel drive control ECU records DTCs when the ECU detects a malfunction in the ECU itself or in system circuits.
The DTCs can be read through the DLC3 of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform troubleshooting.
2. CHECK DLC3
(a) Inspect the battery voltage.
Standard voltage:
11 to 14 V
If the voltage is below 11 V, recharge the battery before proceeding.
(b) Check the DLC3 (See page .gif)
).
3. FUNCTION OF INDICATOR LIGHT
(a) When a problem occurs in the touch select 2-4 and high-low system, a message is displayed on the multi-information display and/or the 4LO indicator light on the combination meter assembly rapidly blinks* to inform the driver of the problem.
- *: 0.25 second intervals (0.25 seconds on and 0.25 seconds off)
(b) Indicator light status (illumination and blinking) or multi-information display status when DTC is output.
TOUCH SELECT 2-4 AND HIGH-LOW SYSTEM|
DTC No. |
4WD Indicator Light (Green) |
4LO Indicator Light |
Multi-information Display Message |
|---|---|---|---|
|
U0100 |
When 2WD: Not illuminated When H4 or L4: Illuminated |
Rapidly blinking |
- |
|
U0122 |
Not illuminated |
Rapidly blinking*1 |
2WD-4WD mode change malfunction visit your dealer |
|
U0416 |
|||
|
P163B |
|||
|
P17A0 |
|||
|
P17A4 |
Not illuminated |
Not illuminated |
2WD-4WD mode change malfunction visit your dealer |
|
P17A8 |
Not illuminated |
Rapidly blinking |
2WD-4WD mode change malfunction visit your dealer |
|
P17A9 |
|||
|
P17AA |
|||
|
P17AC |
|||
|
P17C7 |
Not illuminated |
When 2WD or H4: Not illuminated When L4: Illuminated |
2WD-4WD mode change malfunction visit your dealer |
|
P17C8 |
|||
|
P2772 |
When 2WD: Not illuminated When H4 or L4: Illuminated |
Rapidly blinking |
- |
|
P279E |
Not illuminated |
Rapidly blinking |
2WD-4WD mode change malfunction visit your dealer |
Rapidly blinking: Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)
- *1: P163B may also display the 2WD/4WD mode status.
System Diagram
SYSTEM DIAGRAM
Transmitting ECU (Transmitter)
Receiving ECU
Signal
Communication Method
4 wheel drive control ECU
Skid ...
Dtc Check / Clear
DTC CHECK / CLEAR
1. CHECK DTC
(a) Check the DTCs.
(1) Turn the ignition switch off.
(2) Connect the Techstream to the DLC3.
(3) Turn the ignition switch to ON.
(4) Turn the Techstream on.
(5) ...
Other materials:
Vehicle Speed Sensor "A" No Signal (P050031)
DESCRIPTION
Vehicles, which are equipped with ABS (Anti-lock Brake System), detect the vehicle
speed using the skid control ECU (brake actuator assembly) and speed sensors. Each
speed sensor monitors the wheel rotation speed and sends a signal to the skid control
ECU. The skid control ECU con ...
Air Mix Damper Control Servo Motor Circuit (Driver Side) (B1446/46)
DESCRIPTION
This No. 3 air conditioning radiator damper servo sub-assembly (for driver side
air mix) is controlled by the air conditioning amplifier assembly and moves the
air mix damper (for driver side) to the desired position.
DTC No.
DTC Detection Condition
...
IG2 Signal Malfunction (B2788)
DESCRIPTION
This DTC is stored when the steering lock ECU (steering lock actuator or UPR
bracket assembly) detects an IG2 power supply malfunction.
HINT:
The steering lock ECU (steering lock actuator or UPR bracket assembly) is not
connected to the CAN communication system. However, the steer ...
