Toyota Tacoma manuals

Toyota Tacoma 2015-2018 Service Manual: Terminals Of Ecu

TERMINALS OF ECU

1. CHECK TIRE PRESSURE WARNING ECU AND RECEIVER

(a) Disconnect the T14 tire pressure warning ECU and receiver connector and measure the voltage and resistance on the wire harness side.

Text in Illustration

*A

w/o Wireless Door Lock System

*B

w/o Smart Key System with Wireless Door Lock System

*C

w/ Smart Key System

*a

Front view of wire harness connector

(to Tire Pressure Warning ECU and Receiver)

w/o Wireless Door Lock System

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

T14-1 (IG) - T14-12 (GND)

LG - W-B

IG power source

Ignition switch ON

10 to 16 V

T14-12 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

w/o Smart Key System with Wireless Door Lock System

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

T25-1 (IG) - T25-12 (GND)

LG - W-B

IG power source

Ignition switch ON

10 to 16 V

T25-7 (+B) - T25-12 (GND

BE - W-B

Power supply (from battery)

Always

10 to 16 V

T25-12 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

w/ Smart Key System

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

T24-1 (IG) - T24-12 (GND)

LG - W-B

IG power source

Ignition switch ON

10 to 16 V

T24-7 (+B) - T24-12 (GND)

BE - W-B

Power supply (from battery)

Always

10 to 16 V

T24-12 (GND) - Body ground*1

W-B - Body ground

Ground

Always

Below 1 Ω

(b) Connect the T14*1, T25*2, T24*3 tire pressure warning ECU and receiver connector.

(c) Measure the voltage and resistance according to the value(s) in the table below. If the result is not as specified, the ECU may be malfunctioning.

HINT:

Measure the values on the wire harness side while the connector is connected.

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

T14-3 (CLSW) - T14-12 (GND)*1

T25-3 (CLSW) - T25-12 (GND)*2

T24-3 (CLSW) - T24-12 (GND)*3

R - W-B

Tire pressure warning reset switch

  • Ignition switch ON
  • Tire pressure warning reset switch on

Below 1.5 V

  • Ignition switch ON
  • Tire pressure warning reset switch off

8 to 15 V

T14-4 (RDA) - T14-12 (GND)*1

T25-4 (RDA) - T25-12 (GND)*2

T24-4 (RDA) - T24-12 (GND)*3

B - W-B

Output signals

Ignition switch ON

Pulse generation (see waveform 1)

T14-5 (PRG) - T14-12 (GND)*1

T25-5 (PRG) - T25-12 (GND)*2

T24-5 (PRG) - T24-12 (GND)*3

GR - W-B

Input signals

Ignition switch ON

Pulse generation (see waveform 1)

  • *1: w/o Wireless Door Lock System
  • *2: w/o Smart Key System with Wireless Door Lock System
  • *3: w/ Smart Key System

(d) Using an oscilloscope, check waveform 1.

Waveform 1:

Waveform 1:

Item

Contents

Terminal

T14-4 (RDA) - T14-12 (GND)*1

T25-4 (RDA) - T25-12 (GND)*2

T24-4 (RDA) - T24-12 (GND)*3

T14-5 (PRG) - T14-12 (GND)*1

T25-5 (PRG) - T25-12 (GND)*2

T24-5 (PRG) - T24-12 (GND)*3

Tool setting

5 V/DIV., 5 ms./DIV.

Vehicle condition

Ignition switch ON

  • *1: w/o Wireless Door Lock System
  • *2: w/o Smart Key System with Wireless Door Lock System
  • *3: w/ Smart Key System
Text in Illustration

*a

Example

*b

GND

HINT:

The waveform shown in the illustration is an example. If the tester displays a waveform that alternates between high and low, where high is a voltage that is between the IG power source voltage and a voltage 2.2 V lower than the IG power source voltage, and where low is a voltage of between 0 and 1.2 V, the ECU can be judged normal.

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 ...

Test Mode Procedure
TEST MODE PROCEDURE 1. TEST MODE (SIGNAL CHECK MODE) PROCEDURE HINT: When entering test mode (signal check mode), the tire pressure warning ECU and receiver stores all the test mode (si ...

Other materials:

Power Source Mode does not Change to ON (IG)
DESCRIPTION If the engine switch is pressed with the electrical key transmitter sub-assembly in the cabin, the certification ECU (smart key ECU assembly) receives a signal and changes the power source mode. HINT: When the cable is disconnected and reconnected to the negative (-) battery termi ...

Wireless remote control battery
Replace the battery with a new one if it is discharged. ■ You will need the following items: Lithium battery CR2032 ■ Replacing the battery Remove the cover using a coin protected with tape etc. Remove the discharged transmitter battery. Insert a new battery with the “+” te ...

Dtc Check / Clear
DTC CHECK / CLEAR 1. CHECK DTC (CHECK USING TECHSTREAM) (a) Connect the Techstream to the DLC3. (b) Turn the ignition switch to ON. (c) Turn the Techstream on. (d) Enter the following menus: Body Electrical / Navigation System / Trouble Codes. (e) Check for DTCs, and then write them down. ( ...

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