Toyota Tacoma manuals

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 3. INSPECT BATTERY VOLTAGE ).

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

(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:

Low Power Supply Voltage Malfunction (C1241)
DESCRIPTION If there is a problem with the skid control ECU (master cylinder solenoid) power supply circuit, the skid control ECU outputs the DTC and prohibits operation under the fail-safe function. If the voltage supplied to terminal IG1 is not within the DTC detection threshold due to mal ...

A-TRAC Indicator Light Remains ON
DESCRIPTION This is the A-TRAC main switch circuit. When the A-TRAC switch is turned on with the transfer in L4, the A-TRAC function is available and the A-TRAC indicator light illuminates. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: When replacing the skid control ECU (master ...

Open in One Side of Bus 2 Branch Line
DESCRIPTION When the CAN bus main lines are normal (no open, short to ground, short to +B or short between lines) and there is an ECU or sensor on the "Communication Bus Check" screen that is indicated as not communicating or whose connection status on the "Communication Bus Ch ...

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