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
).
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
Dtc Check / ClearLost 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 ...
General Information
GENERAL INFORMATION
A large number of ECU controlled systems are used in the TOYOTA TACOMA.
In general, ECU controlled systems are considered to be very intricate,
requiring a high level of technical knowledge to troubleshoot. However,
most problem checking procedures only involv ...
Automatic High Beam System does not Operate or Operation Indicator does not
Illuminate
DESCRIPTION
The main body ECU (multiplex network body ECU) controls the automatic high beam
system based on signals received from the forward recognition camera.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
When replacing the combination meter assembly, always replace it with
...