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Toyota Tacoma (2015-2018) Service Manual / 2gr-fks Starting / Smart Key System(for Start Function) / Power Source Mode does not Change to ON (IG and ACC)

Toyota Tacoma (2015-2018) Service Manual: Power Source Mode does not Change to ON (IG and ACC)

DESCRIPTION

If any of the following operations are performed, the certification ECU (smart key ECU assembly) receives a signal, and changes the power source mode.

  • With the electrical key transmitter sub-assembly in the cabin, the engine switch is pressed.
  • When the battery of the electrical key transmitter sub-assembly is depleted, the brake pedal is depressed and the electrical key transmitter sub-assembly is held near the engine switch.
  • When the smart key cancel function has been canceled on the customization menu, the brake pedal is depressed and the electrical key transmitter sub-assembly is held near the engine switch.

HINT:

  • When the cable is disconnected and reconnected to the negative (-) battery terminal, the power source mode returns to the state it was in before the cable was disconnected.
  • If the room oscillator does not recognize the key, the cause of the malfunction may be stored in the certification ECU (smart key ECU assembly) (See page If the cause of the malfunction is stored in the certification ECU (smart ).
  • If the cause of the malfunction is stored in the certification ECU (smart key ECU assembly), the following table is helpful in checking whether or not the malfunction was caused by wave interference.
Radio Wave Interference:

Problem Symptom

Data List Item

Operating Engine Switch / Key RF Signal Interference
  • When the engine switch was operated, the electrical key transmitter sub-assembly could not be confirmed due to wave interference. Therefore, the output frequency was switched to the other channel (changed from channel 1 to channel 2 or from channel 2 to channel 1).
  • If the cause of the malfunction has not been stored but any devices that can cause wave interference in the cabin have been removed and the room oscillator successfully recognizes the key, the possibility of wave interference is high.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION / NOTICE / HINT

NOTICE:

  • When using the Techstream with the engine switch off, connect the Techstream to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the Techstream and the vehicle begins. Then select the vehicle type under manual mode and enter the following menus: Body Electrical / Smart Key. While using the Techstream, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the Techstream and the vehicle.
  • The smart key system (for Start Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting.

    Click here Troubleshoot the smart key system (for Start Function) after confirming

    Troubleshoot the smart key system (for Start Function) after confirming that the communication systems are functioning properly.

  • Make sure that no DTCs are output. If any DTCs are output, proceed to the Diagnostic Trouble Code Chart (See page If the smart key system is disabled through the customize function, ).
  • If the smart key system is disabled through the customize function, enable the system before performing troubleshooting (See page Before replacing the certification ECU (smart key ECU assembly) or electrical ).
  • Before replacing the certification ECU (smart key ECU assembly) or electrical key transmitter sub-assembly, refer to the smart key system (for Start Function) precaution (See page Inspect the fuses of circuits related to this system before performing ).
  • Inspect the fuses of circuits related to this system before performing the following inspection procedure.
  • After completing repairs, confirm that the problem does not occur.
Related Data List and Active Test Items

Problem Symptom

Data List Item

Active Test Item

Power source mode does not change to on (IG) or on (ACC)
Power Source Control
  • Start Switch1
  • Start Switch2
  • Power Supply Condition
  • IG Relay Monitor(Inside)
  • IG Relay Monitor (Outside)
  • Latch Circuit
  • ACC Relay Monitor

-

PROCEDURE

1.

CHECK ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY

(a) Press a switch of the electrical key transmitter sub-assembly.

OK:

The electrical key transmitter sub-assembly LED illuminates.

NG

GO TO STEP 14

OK

2.

READ VALUE USING TECHSTREAM (KEY LOW BATTERY)

(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 / Data List.

(e) Read the Data List according to the display on the Techstream.

Smart Key

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Key Low Battery

Transmitter battery depleted / Yes or No

Yes: Transmitter battery depleted

No: Transmitter battery not depleted

The electrical key transmitter sub-assembly sends voltage information to the certification ECU (smart key ECU assembly) when it is transmitting. The certification ECU (smart key ECU assembly) displays "Yes" for the "Key Low Battery" item of the Data List when this voltage information indicates 2.2 V or less. This Data List item should be checked when the electrical key transmitter sub-assembly is at room temperature (example: at -20°C (-4°F), "Yes" may be displayed even if the transmitter battery is new).

OK:

"No" is displayed on the Techstream screen.

NG

REPLACE TRANSMITTER BATTERY

OK

3.

CHECK POWER SOURCE MODE

(a) Get into the vehicle while carrying an electrical key transmitter sub-assembly.

(b) Move the shift lever to P.

(c) Press the engine switch with the brake pedal released and check that the power source mode changes.

Result

Result

Proceed to

The power source mode does not change

A

The power source mode changes

B
B

END (AFFECTED BY WAVE INTERFERENCE)
A

4.

CHECK SMART KEY SYSTEM (for StartFunction)

(a) Remove the transmitter battery from the electrical key transmitter sub-assembly.

(b) With the brake pedal depressed, hold the electrical key transmitter sub-assembly near the engine switch and check if the power source mode changes.

OK:

The power source mode changes.

Text in Illustration

*1

Engine Switch

*2

Electrical Key Transmitter Sub-assembly
Result

Result

Proceed to

The power source mode does not change

A

The power source mode changes

B

HINT:

If the power source mode changes, the cabin verification is malfunctioning.
B

GO TO STEP 11

A

5.

CHECK FOR DTC

(a) Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs (See page Result ).

Result

Result

Proceed to

DTCs are not output

A

Smart key system (for Start Function) DTCs are output

B
B

GO TO DIAGNOSTIC TROUBLE CODE CHART

A

6.

CHECK HARNESS AND CONNECTOR (POWER SOURCE)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE
OK

7.

CHECK HARNESS AND CONNECTOR (GROUND)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

8.

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - DRIVER SIDE JUNCTION BLOCK)

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

(b) Disconnect the 1A and 1D driver side junction block connectors.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

C29-9 (ACCD) - 1A-28

Always

Below 1 Ω

C27-3 (IG1D) - 1A-16

Always

Below 1 Ω

1D-5 - Body ground

Always

Below 1 Ω

C29-9 (ACCD) or 1A-28 - Body ground

Always

10 kΩ or higher

C27-3 (IG1D) or 1D-16 - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

9.

CHECK DRIVER SIDE JUNCTION BLOCK (IG1 NO. 1, IG1 NO. 2, IG1 NO. 3, ACC RELAY)

(a) Remove the driver side junction block (See page (b) Measure the resistance according to the value(s) in the table below. ).

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

Text in Illustration

*a

Component without harness connected

(Driver Side Junction Block)

-

-

Standard Resistance:

Tester Connection

Condition

Specified Condition

1A-16 - 1D-5

20°C (68°F)

87.32 to 127.14 Ω

1A-28 - 1D-5

20°C (68°F)

130.92 to 190.74 Ω

1K-1 - 1F-1

Battery voltage applied to terminals 1A-16 and 1D-5

Below 1 Ω

Battery voltage not applied to terminals 1A-16 and 1D-5

10 kΩ or higher

1K-1 - 1D-4

Battery voltage applied to terminals 1A-16 and 1D-5

Below 1 Ω

Battery voltage not applied to terminals 1A-16 and 1D-5

10 kΩ or higher

1K-1 - 1F-12

Battery voltage applied to terminals 1A-16 and 1D-5

Below 1 Ω

Battery voltage not applied to terminals 1A-16 and 1D-5

10 kΩ or higher

1K-1 - 1F-24

Battery voltage applied to terminals 1A-28 and 1D-5

Below 1 Ω

Battery voltage not applied to terminals 1A-28 and 1D-5

10 kΩ or higher
NG

REPLACE DRIVER SIDE JUNCTION BLOCK

OK

10.

CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

(a) Install the driver side junction block (See page (b) Connect the C29 and C27 certification ECU (smart key ECU assembly) connectors. ).

(b) Connect the C29 and C27 certification ECU (smart key ECU assembly) connectors.

(c) Measure the voltage while confirming the power source mode on the Data List.

Text in Illustration

*a

Component with harness connected

(Certification ECU (Smart Key ECU Assembly))

-

-
Power Source Control

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Power Supply Condition

Power supply state / All OFF, ACC ON, IG ON or ST ON

All OFF: Engine switch off (ACC and IG)

ACC ON: Engine switch on (ACC)

IG ON: Engine switch on (IG)

ST ON: Sending engine start request signal

-

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

C27-3 (IG1D) - Body ground

Engine switch off

1 V or less

Engine switch on (ACC)

1 V or less

Engine switch on (IG)

9 V or higher

C29-9 (ACCD) - Body ground

Engine switch off

1 V or less

Engine switch on (ACC)

8.5 V or higher

Engine switch on (IG)

8.5 V or higher
Result

Result

Proceed to

NG

A

OK

B
B

USE SIMULATION METHOD TO CHECK

A

11.

READ VALUE USING TECHSTREAM (START SWITCH1, START SWITCH2)

(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 / Power Source Control / Data List.

(e) Read the Data List according to the display on the Techstream.

Power Source Control

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Start Switch1

Engine switch 1 status / ON or OFF

ON: Engine switch pressed

OFF: Engine switch not pressed
  • If the engine switch is pressed for a short time, the display may not change.
  • Use this item to determine whether the engine switch input signal is malfunctioning.

Start Switch2

Engine switch 2 status / ON or OFF

ON: Engine switch pressed

OFF: Engine switch not pressed
  • Backup for engine switch 1. However, when the engine switch is pressed and held, the control functions only when both engine switch 1 and 2 are normal.
  • Behaves the same way as engine switch 1.

OK:

The Techstream display changes correctly in response to the engine switch operation.

Result

Result

Proceed to

NG

A

OK

B
B

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

A

12.

INSPECT ENGINE SWITCH

(a) Remove the engine switch (See page (b) Inspect the engine switch (See page ). ).

(b) Inspect the engine switch (See page ).

NG

REPLACE ENGINE SWITCH

OK

13.

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ENGINE SWITCH)

(a) Disconnect the C29 certification ECU (smart key ECU assembly) connector.

(b) Disconnect the E28 engine switch connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

C29-16 (SSW1) - E28-5 (SS1)

Always

Below 1 Ω

C29-18 (SSW2) - E28-1 (SS2)

Always

Below 1 Ω

C29-12 (AGND) - E28-6 (AGND)

Always

Below 1 Ω

C29-16 (SSW1) or E28-5 (SS1) - Body ground

Always

10 kΩ or higher

C29-18 (SSW2) or E28-1 (SS2) - Body ground

Always

10 kΩ or higher

C29-12 (AGND) or E28-6 (AGND) - Body ground

Always

10 kΩ or higher
OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

14.

INSPECT TRANSMITTER BATTERY

(a) Inspect the transmitter battery (See page ). ).

NOTICE:

Do not wrap the lead wire around a terminal, wedge it between terminals, or solder it. The terminal may be deformed or damaged, and the transmitter battery will not be able to be installed correctly.

OK

REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY
NG

REPLACE TRANSMITTER BATTERY

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