Toyota Tacoma (2015-2018) Service Manual: Diagnosis System

Toyota Tacoma (2015-2018) Service Manual / Door Lock / Wireless Door Lock Control System(w/ Smart Key System) / 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).

(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:

Pattern Select Switch Power Mode Circuit
DESCRIPTION The ECM memory contains the programs for the normal and PWR shift patterns. By following the programs corresponding to the signals from the pattern select switch assembly, park/neutral position switch and other various sensors, the ECM switches the shift solenoid valves on and off, ...

Downhill Assist Control Switch Malfunction (Test Mode DTC) (C1379)
DESCRIPTION DTC C1379 is cleared when the crawl control switch sends a crawl control operation signal or when test mode ends. DTC Code DTC Detection Condition Trouble Area C1379 Stored only during test mode. Crawl ...

Transponder Chip Malfunction (B2793,B2794,B2797,B2798)
DESCRIPTION DTC B2793 is stored when a malfunction is found in the key during key code registration or a key code is not registered normally. Replace the key if key code registration cannot be performed normally and this DTC is output. DTC B2794 is stored when a key with an i ...