Toyota Tacoma (2015-2018) Service Manual: Diagnosis System
DIAGNOSIS SYSTEM
1. DESCRIPTION
(a) When troubleshooting a vehicle with a diagnosis system, the only difference from the usual troubleshooting procedure is connecting the Techstream to the vehicle and reading various data output from the clearance warning ECU assembly.
The clearance warning ECU assembly stores DTCs when the ECU detects a malfunction in the ECU itself or in its circuits.
To check the DTCs, connect the Techstream to the DLC3 on the vehicle. The Techstream makes it possible to clear the DTCs, activate the various actuators, and check the freeze frame data and Data List.
2. CHECK DLC3
(a) Check the DLC3 (See page .gif)
).
Terminals Of Ecu
TERMINALS OF ECU
1. CLEARANCE WARNING ECU ASSEMBLY
(a) Disconnect the C30 connector from the clearance warning ECU assembly.
(b) Measure the voltage and resistance according to the value(s) in th ...
Dtc Check / Clear
DTC CHECK / CLEAR
1. CHECK DTC
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the back sonar or clearance sonar switch assembly on.
(d) Turn the Techstream o ...
Other materials:
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 ...
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
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 listed in order
of probability in the "Suspected Area" column of the table. Check each symptom by
checking the ...
On-vehicle Inspection
ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT INDICATOR LIGHT
(a) Inspect the 4HI Indicator Light:
(1) Start the engine.
(2) Change the 4WD control switch from 2WD to 4H.
(3) Check the 4HI indicator light.
OK:
The 4HI indicator light comes on or the 4HI indicator light comes on after it
is b ...
