Toyota Tacoma manuals

Toyota Tacoma 2015-2018 Service Manual: Terminals Of Ecu

TERMINALS OF ECU

1. CHECK ENGINE SWITCH

(a) Measure the resistance and voltage according to the value(s) in the table

(a) Measure the resistance and voltage according to the value(s) in the table below.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

E28-6 (AGND) - Body ground

-

Y - Body ground

Transponder key amplifier ground

Always

Below 1 Ω

-

E28-7 (TXCT) - E28-6 (AGND)

Input

R - Y

Immobiliser communication input

Engine switch off, brake pedal not depressed, 30 seconds or more elapsed after driver door opened and then closed

Below 1 V

-

E28-8 (CODE) - E28-6 (AGND)

Output

SB - Y

Immobiliser communication output

Engine switch off, brake pedal not depressed, 30 seconds or more elapsed after driver door opened and then closed

Below 1 V

-

E28-10 (VC5) - E28-6 (AGND)

Input

W - Y

Transponder key amplifier power supply

Engine switch off, brake pedal not depressed, 30 seconds or more elapsed after driver door opened and then closed

Below 1 V

-

(b) Check for pulses according to the value(s) in the table below.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

E28-7 (TXCT) - E28-6 (AGND)

Input

R - Y

Signal input from certification ECU (smart key ECU assembly)

(Code sent from certification ECU (smart key ECU assembly) to transponder key amplifier built into engine switch, and then transmitted by transponder key amplifier antenna as radio waves)

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

Pulse generation

(See waveform 1)

  • BCC Malfunction
  • Abnormal Status
  • Different Encrypt Code
  • Different Serial Number
  • Frame Error
  • Response

    HINT:

    If immobiliser key code certification communication is not performed correctly, the malfunction may be indicated by one or more of the Data List items listed above

E28-8 (CODE) - E28-6 (AGND)

Output

SB - Y

Signal output to certification ECU (smart key ECU assembly)

(Radio waves from transponder key amplifier built into engine switch used to detect key information. Key information then sent to certification ECU (smart key ECU assembly))

Engine switch off, engine switch pressed with key held near engine switch*

Pulse generation

(See waveform 2)

E28-10 (VC5) - E28-6 (AGND)

Input

W - Y

Transponder key amplifier power supply

(Power supplied from certification ECU (smart key ECU assembly) when transponder key amplifier built into engine switch activated)

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

Pulse generation

(See waveform 3)

If the result is not as specified, the engine switch may be malfunctioning.

HINT:

*: Remove the key battery before performing this inspection.

(c) Inspect using an oscilloscope.

NOTICE:

The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

(1) Waveform 1 (Reference)

Measurement Condition

Item

Content

Tester Connection

E28-7 (TXCT) - E28-6 (AGND)

Tool Setting

2 V/DIV., 20 ms./DIV.

Condition

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

(2) Waveform 2 (Reference)

Text in Illustration

*a

Waveform

*b

Waveform (detail)

Measurement Condition

Item

Content

Tester Connection

E28-8 (CODE) - E28-6 (AGND)

Tool Setting

  • Waveform

    1 V/DIV., 20 ms./DIV.

  • Waveform (detail)

    2 V/DIV., 100 μs./DIV.

Condition

Engine switch off, engine switch pressed with key held near engine switch*

HINT:

*: Remove the key battery before performing this inspection.

(3) Waveform 3 (Reference)

Measurement Condition

Item

Content

Tester Connection

E28-10 (VC5) - E28-6 (AGND)

Tool Setting

2 V/DIV., 200 ms./DIV.

Condition

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

(a) Disconnect the C27 and C29 certification ECU (smart key ECU assembly) connectors.

(a) Disconnect the C27 and C29 certification ECU (smart key ECU assembly) connectors.

(b) Measure the resistance and voltage according to the value(s) in the table below.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

C29-10 (+B) - C29-11 (E)

Input

P - W-B

+B power supply

Always

11 to 14 V

-

C27-4 (CUTB) - C29-11 (E)

Input

GR - W-B

Dark current cut pin

Always

11 to 14 V

-

C29-11 (E) - Body ground

-

W-B - Body ground

Ground

Always

Below 1 Ω

-

(c) Reconnect the C27 and C29 certification ECU (smart key ECU assembly) connectors.

(d) Measure the resistance and voltage according to the value(s) in the table below.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

C27-3 (IG1D) - C29-11 (E)

Input

B - W-B

Ignition power supply

Engine switch off → on (IG)

Below 1 V → 11 to 14 V

Ignition Switch

C29-19 (IND) - C29-11 (E)

Output

V - W-B

Security indicator output

Engine switch off → on (IG)

Pulse generation

→ Below 2 V

-

C29-14 (TXCT) - C29-12 (AGND)

Output

R - Y

Signal output to transponder key amplifier

Engine switch off, brake pedal not depressed, 30 seconds or more elapsed after driver door opened and then closed

Below 1 V

  • BCC Malfunction
  • Abnormal Status
  • Different Encrypt Code
  • Different Serial Number
  • Frame Error
  • Response

C29-13 (CODE) - C29-12 (AGND)

Input

SB - Y

Signal input from transponder key amplifier

Engine switch off, brake pedal not depressed, 30 seconds or more elapsed after driver door opened and then closed

Below 1 V

C29-15 (VC5) - C29-12 (AGND)

Output

W - Y

Transponder key amplifier power supply

Engine switch off, brake pedal not depressed, 30 seconds or more elapsed after driver door opened and then closed

Below 1 V

C29-12 (AGND) - Body ground

-

Y - Body ground

Transponder key amplifier ground

Always

Below 1 Ω

C27-7 (EFII) - C29-11 (E)

Input

Y - W-B

EFI communication input

(Signal input from ECM to certification ECU (smart key ECU assembly))

Engine switch off

11 to 14 V

  • B2799
  • B279A
  • Engine Start Request
  • EFI Code Receive

C27-6 (EFIO) - C29-11 (E)

Output

SB - W-B

EFI communication output

(Signal output from certification ECU (smart key ECU assembly) to ECM)

Engine switch off

11 to 14 V

(e) Check for pulses according to the value(s) in the table below.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

C29-14 (TXCT) - C29-12 (AGND)

Output

R - Y

Signal output to transponder key amplifier

(Code sent from certification ECU (smart key ECU assembly) to transponder key amplifier built into engine switch, and then transmitted by transponder key amplifier antenna as radio waves)

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

Pulse generation

(See waveform 1)

  • BCC Malfunction
  • Abnormal Status
  • Different Encrypt Code
  • Different Serial Number
  • Frame Error
  • Response

C29-13 (CODE) - C29-12 (AGND)

Input

SB - Y

Signal input from transponder key amplifier

(Radio waves from transponder key amplifier built into engine switch used to detect key information. Key information then sent to certification ECU (smart key ECU assembly))

Engine switch off, engine switch pressed with key held near engine switch*

Pulse generation

(See waveform 2)

C29-15 (VC5) - C29-12 (AGND)

Output

W - Y

Transponder key amplifier power supply

(Power supplied from certification ECU (smart key ECU assembly) when transponder key amplifier built into engine switch activated)

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

Pulse generation

(See waveform 3)

C27-7 (EFII) - C29-11 (E)

Input

Y - W-B

EFI communication input

(Signal input from ECM to certification ECU (smart key ECU assembly))

Within 3 seconds of engine start or within 3 seconds of engine switch turned on (IG) after battery cable disconnected and reconnected

Pulse generation

(See waveform 4)

  • B2799
  • B279A
  • Engine Start Request
  • EFI Code Receive

C27-6 (EFIO) - C29-11 (E)

Output

SB - W-B

EFI communication output

(Signal output from certification ECU (smart key ECU assembly) to ECM)

Engine switch on (IG) using registered electrical key transmitter sub-assembly

Pulse generation

(See waveform 5)

If the result is not as specified, the certification ECU (smart key ECU assembly) may be malfunctioning.

HINT:

*: Remove the key battery before performing this inspection.

(f) Inspect using an oscilloscope.

NOTICE:

The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

(1) Waveform 1 (Reference)

Measurement Condition

Item

Content

Tester Connection

C29-14 (TXCT) - C29-12 (AGND)

Tool Setting

2 V/DIV., 20 ms./DIV.

Condition

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

(2) Waveform 2 (Reference)

Text in Illustration

*a

Waveform

*b

Waveform (detail)

Measurement Condition

Item

Content

Tester Connection

C29-13 (CODE) - C29-12 (AGND)

Tool Setting

  • Waveform

    1 V/DIV., 20 ms./DIV.

  • Waveform (detail)

    2 V/DIV., 100 μs./DIV.

Condition

Engine switch off, engine switch pressed with key held near engine switch*

HINT:

*: Remove the key battery before performing this inspection.

(3) Waveform 3 (Reference)

Measurement Condition

Item

Content

Tester Connection

C29-15 (VC5) - C29-12 (AGND)

Tool Setting

2 V/DIV., 200 ms./DIV.

Condition

Engine switch off, key not in cabin, within 30 seconds after engine switch pressed

(4) Waveform 4 (Reference)

Text in Illustration

*a

Approximately 160 ms

*b

Approximately 270 ms

Measurement Condition

Item

Content

Tester Connection

C27-7 (EFII) - C29-11 (E)

Tool Setting

2 V/DIV., 500 ms./DIV.

Condition

Within 3 seconds of engine start or within 3 seconds of engine switch turned on (IG) after battery cable disconnected and reconnected

(5) Waveform 5 (Reference)

Text in Illustration

*a

Approximately 160 ms

*b

Approximately 270 ms

Measurement Condition

Item

Content

Tester Connection

C27-6 (EFIO) - C29-11 (E)

Tool Setting

2 V/DIV., 500 ms./DIV.

Condition

Engine switch on (IG) using registered electrical key transmitter sub-assembly

3. CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPR BRACKET ASSEMBLY)

(a) Measure the voltage and resistance according to the value(s) in the table

(a) Measure the voltage and resistance according to the value(s) in the table below.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

S45-1 (GND) - Body ground

-

W-B - Body ground

Ground

Always

Below 1 Ω

-

S45-3 (IGE) - S45-1 (GND)

Input

Y - W-B

Steering lock motor operation permission signal (motor operation permission signal supplied by certification ECU (smart key ECU assembly))

Steering lock motor operates when all conditions met, and then door opened:

  • Shift lever in P
  • Steering unlocked
  • Engine switch turned off

Pulse generation

(See waveform 1)

  • Power Supply Short
  • Unlock Request Receive
  • Lock Request Receive

S45-4 (SLP1) - S45-1 (GND)

Output

BE - W-B

Steering lock bar position signal (signal output from steering unlock sensor)

Steering locked → unlocked*1

11 to 14 V → Below 1.5 V

  • Push Start Error
  • Sensor Value

S45-6 (IG2) - S45-1 (GND)

Input

B - W-B

IG signal (IG2 power supply input for steering lock motor)

Engine switch off → on (IG)

Below 1 V → 11 to 14 V

  • B2788
  • Ignition Switch

S45-7 (B) - Body ground

Output

R - Body ground

Constant power supply

Always

11 to 14 V

B2788

If the result is not as specified, the steering lock ECU (steering lock actuator or upr bracket assembly) may be malfunctioning.

HINT:

*1: The steering locks when any door is opened with the shift lever in P and the engine switch off. The steering unlocks when the engine switch is turned on (ACC).

(b) Inspect using an oscilloscope.

NOTICE:

The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

(1) Waveform 1 (Reference)

Text in Illustration

*a

Steering lock motor not operating

*b

Steering lock motor operating

Measurement Condition

Item

Content

Tester Connection

S45-3 (IGE) - S45-1 (GND)

Tool Setting

2 V/DIV., 200 ms./DIV.

Condition

Steering lock motor operates when all conditions met, and then door opened:

  • Shift lever in P
  • Steering unlocked
  • Engine switch turned off

4. CHECK ECM

HINT:

HINT:

The standard voltage between each pair of ECM terminals is shown in the table below. The appropriate conditions for checking each pair of terminals are also indicated. The result of checks should be compared with the standard voltage for that pair of terminals, displayed in the "Specified Condition" column. The illustration above can be used as a reference to identify the ECM terminal locations.

Terminal No. (Symbol)

Input/Output

Wiring Color

Terminal Description

Condition

Specified Condition

Related Data List Item/DTC

E11-1 (E1) - Body ground

-

W-B - Body ground

Ground

Always

Below 1 Ω

-

E14-2 (BATT) - E11-1 (E1)

Input

L - W-B

+B power supply

Always

11 to 14 V

-

E14-3 (+B) - E11-1 (E1)

Input

B - W-B

+B power supply

Engine switch on (IG)

11 to 14 V

-

E14-4 (+B2) - E11-1 (E1)

Input

B - W-B

+B power supply

Engine switch on (IG)

11 to 14 V

-

E14-9 (IMO) - E11-1 (E1)

Input

Y - W-B

Certification ECU (smart key ECU assembly) communication input

Engine switch off

11 to 14 V

-

E14-9 (IMO) - E11-1 (E1)

Input

Y - W-B

Certification ECU (smart key ECU assembly) communication input

Within 3 seconds of engine start or within 3 seconds of engine switch turned on (IG) after battery cable disconnected and reconnected

Pulse generation

(See waveform 1)

-

E14-8 (IMI) - E11-1 (E1)

Output

SB - W-B

Certification ECU (smart key ECU assembly) communication output

Engine switch off

11 to 14 V

-

E14-8 (IMI) - E11-1 (E1)

Output

SB - W-B

Certification ECU (smart key ECU assembly) communication output

Engine switch on (IG) using registered electrical key transmitter sub-assembly

Pulse generation

(See waveform 2)

-

(a) Inspect using an oscilloscope.

NOTICE:

The waveform shown in the illustration is an example for reference only. Noise, chattering, etc. are not shown.

(1) Waveform 1 (Reference)

Text in Illustration

*a

Approximately 160 ms

*b

Approximately 270 ms

Measurement Condition

Item

Content

Tester Connection

E14-9 (IMO) - E11-1 (E1)

Tool Setting

2 V/DIV., 500 ms./DIV.

Condition

Within 3 seconds of engine start or within 3 seconds of engine switch turned on (IG) after battery cable disconnected and reconnected

(2) Waveform 2 (Reference)

Text in Illustration

*a

Approximately 160 ms

*b

Approximately 270 ms

Measurement Condition

Item

Content

Tester Connection

E14-8 (IMI) - E11-1 (E1)

Tool Setting

2 V/DIV., 500 ms./DIV.

Condition

Engine switch on (IG) using registered electrical key transmitter sub-assembly

Dtc Check / Clear
DTC CHECK / CLEAR 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 1.5 se ...

Data List / Active Test
DATA LIST / ACTIVE TEST 1. DATA LIST NOTICE: In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when dec ...

Other materials:

Emission inspection and maintenance (I/M) programs
Some states have vehicle emission inspection programs which include OBD (On Board Diagnostics) checks. The OBD system monitors the operation of the emission control system. ■ If the malfunction indicator lamp comes on The OBD system determines that a problem exists somewhere in the emiss ...

Front Fog Light Circuit
DESCRIPTION The main body ECU (multiplex network body ECU) controls the front fog lights. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this system before performing the following inspection procedure. If the main body ECU (multiplex ...

Electronic Circuit Inspection Procedure
ELECTRONIC CIRCUIT INSPECTION PROCEDURE 1. BASIC INSPECTION (a) WHEN MEASURING RESISTANCE OF ELECTRONIC PARTS (1) Unless otherwise stated, all resistance measurements should be made at an ambient temperature of 20°C (68°F). Resistance measurements may be inaccurate if measured at high tempe ...

© 2011-2021 Copyright www.ttguide.net