Toyota Tacoma (2015-2018) Service Manual: Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
The ECU stores trouble codes when malfunctions occur.
The diagnostic system allows for reading of the trouble codes from the DLC3.
Use the Techstream to help diagnose and repair the problem.
2. CHECK DLC3
(a) Check the DLC3 (See page .gif)
).
3. INSPECT BATTERY VOLTAGE
(a) Measure the battery voltage.
Standard voltage:
11 to 14 V
If the voltage is below 11 V, recharge or replace the battery.
4. SELF-DIAGNOSTIC MODE
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Smart Key / Utility / Wireless Door Lock Diagnosis Mode.
(e) Proceed to the next step in accordance with the prompts on the Techstream screen.
HINT:
The electrical key transmitter uses 2 different frequencies alternately for communication. When in self diagnostic mode, one of the channels can be selected or the channels can be automatically switched.
(f) Check that the system has switched to self-diagnostic mode by checking the wireless door lock buzzer output pattern.
(g) Check the diagnostic outputs when the electrical key transmitter sub-assembly switch is held down.
The diagnostic outputs can be checked by the interior light and wireless door lock buzzer patterns.
Result
|
Wireless Door Lock Buzzer Output |
Suspected Area |
|---|---|
|
A |
Normal (No malfunction) |
|
B |
Register wireless code |
|
C |
Wave interference or malfunction of a related component |
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
HINT:
Use the table below to help determine the cause of problem symptoms.
If multiple suspected areas are listed, the potential causes of the symptoms
are lis ...
Dtc Check / Clear
DTC CHECK / CLEAR
1. CHECK FOR DTC
HINT:
When using the Techstream with the engine switch off to troubleshoot:
Connect the Techstream to the DLC3 and turn a courtesy light switch on and off
at 1 ...
Other materials:
Air Fuel Ratio Sensor
Components
COMPONENTS
ILLUSTRATION
Removal
REMOVAL
PROCEDURE
1. REMOVE AIR FUEL RATIO SENSOR (for Bank 1 Sensor 1)
(a) Disconnect the air fuel ratio sensor connector.
(b) Disengage the clamp to separate the air fuel ratio sensor wire ...
Lost Communication with Power Source Control (B278C)
DESCRIPTION
DTC No.
DTC Detection Condition
Trouble Area
B278C
An internal malfunction occurs in the certification ECU (smart key ECU
assembly)
Certification ECU (smart key ECU assembly)
CAUTI ...
Clutch Switch Circuit
DESCRIPTION
Clutch switch circuit inspection is necessary for manual transmission vehicles.
When the clutch pedal is released, the ECM receives the positive (+) battery
voltage through the ECU-IG NO. 2 fuse and ignition switch. While the clutch pedal
is depressed, the clutch switch assembly se ...
