Toyota Tacoma (2015-2018) Service Manual: Driver Side Door Entry Lock and Unlock Functions do not Operate

Toyota Tacoma (2015-2018) Service Manual / Door Lock / Smart Key System(for Entry Function) / Driver Side Door Entry Lock and Unlock Functions do not Operate

DESCRIPTION

If the entry lock and unlock functions do not operate for the driver door only, the request code may not be being transmitted from the driver door or the front door outside handle assembly LH (touch sensor) may be malfunctioning. If the entry functions for other doors operate properly, communication between the electrical key transmitter sub-assembly and electrical key and TPMS receiver assembly is normal.

In this case, there may be a problem with request code transmission (communication between the certification ECU (smart key ECU assembly) and front door outside handle assembly LH [electrical key antenna]), or there may be wave interference.

HINT:

If the driver door entry lock and unlock functions do not operate, 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 key ECU assembly), the following table is helpful in checking whether or not the malfunction was caused by wave interference.

Radio Wave Interference:

Parameter Name	Cause of Problem and Countermeasure
Lock / Key RF Signal Interference	When entry lock operation was performed, the electrical key transmitter sub-assembly could not be confirmed due to wave interference. If the cause of the malfunction has not been stored but the car has been moved and an entry lock operation has been successfully performed, the possibility of wave interference is high.
Unlock / Key RF Signal Interference	When entry unlock operation was performed, the electrical key transmitter sub-assembly could not be confirmed due to wave interference. If the cause of the malfunction has not been stored but the car has been moved and an entry unlock operation has been successfully performed, the possibility of wave interference is high.

Parameter Name

Cause of Problem and Countermeasure

Lock / Key RF Signal Interference

When entry lock operation was performed, the electrical key transmitter sub-assembly could not be confirmed due to wave interference.

If the cause of the malfunction has not been stored but the car has been moved and an entry lock operation has been successfully performed, the possibility of wave interference is high.

Unlock / Key RF Signal Interference

When entry unlock operation was performed, the electrical key transmitter sub-assembly could not be confirmed due to wave interference.

If the cause of the malfunction has not been stored but the car has been moved and an entry unlock operation has been successfully performed, the possibility of wave interference is high.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

The smart key system (for Entry 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. Troubleshoot the smart key system (for Entry Function) after confirming that the communication systems are functioning properly (See page ).
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.
Check that there are no electrical key transmitter sub-assemblies in the vehicle.
Before performing the inspection, check that DTC B1242 (wireless door lock control) is not output (See page ).
Before replacing the certification ECU (smart key ECU assembly), refer to the smart key system (for Entry Function) precaution (See page ).
After repair, confirm that no DTCs are output by performing the "DTC Output Confirmation Operation".

PROCEDURE

1.	CHECK POWER DOOR LOCK CONTROL SYSTEM

(a) When the door control switch on the power window regulator master switch assembly is operated, check that the doors unlock and lock according to the switch operation (See page OK: ).

OK:

Door locks operate normally.

GO TO POWER DOOR LOCK CONTROL SYSTEM

2.	CHECK FOR DTC

(a) Check for DTCs (See page Result ).

Result

Result	Proceed to
DTCs are not output	A
DTCs are output	B

GO TO DIAGNOSTIC TROUBLE CODE CHART

3.	CHECK WAVE ENVIRONMENT

(a) Bring the electrical key transmitter sub-assembly approximately 0.3 m (0.984 ft.) from the front door outside handle assembly LH and perform an entry function check (See page Text in Illustration ).

Text in Illustration

*a	Approximately 0.3 m (0.984 ft.)

HINT:

Communication may not be possible if the electrical key transmitter sub-assembly is within 0.2 m (0.656 ft.) of the front door outside handle assembly LH.
When the electrical key transmitter sub-assembly is brought near the front door outside handle assembly LH, the possibility of wave interference decreases, and it can be determined if wave interference is causing the problem symptom.
If the inspection result is that the problem only occurs in certain locations or at certain times of day, the possibility of wave interference is high. Also, added vehicle components may cause wave interference. If installed, remove them and perform the operation check.
There may be wave interference if the vehicle is near broadcasting antennas, large video displays, wireless garage door opener systems, wireless security cameras, home security systems, etc. In this case, move the vehicle to a different location and check if there is any improvement.
If a tool for checking radio waves, such as a signal strength meter, is available, move around the area while observing both the LF band (used by the vehicle antenna to form the detection area) and RF band (used by the electrical key transmitter sub-assembly for transmission) to check for locations where there is wave interference.
When checking the operation of the entry lock function several times, it can be operated up to 2 times consecutively. To operate the function 3 times or more consecutively, the doors need to be unlocked once. However, this is only for the entry lock function, other door lock operations, such as a wireless door lock operation can be performed consecutively.

Result

Result	Proceed to
Entry function does not operate normally	A
Entry function operates normally	B

AFFECTED BY WAVE INTERFERENCE

4.	READ VALUE USING TECHSTREAM (D-DOOR TOUCH SENSOR, D-DOOR TRIGGER SWITCH)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(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
D-Door Touch Sensor	Driver door touch sensor (unlock sensor) / ON or OFF	ON: Driver door touch sensor (unlock sensor) touched OFF: Driver door touch sensor (unlock sensor) not touched	Displays whether the unlock sensor is on or off (even if the sensor is touched and contact is maintained, "ON" is displayed only momentarily). Use this Data List item to help determine if there is an unlock sensor malfunction when the entry unlock function does not operate.
D-Door Trigger Switch	Driver door touch sensor (lock sensor) / ON or OFF	ON: Driver door touch sensor (lock sensor) touched OFF: Driver door touch sensor (lock sensor) not touched	Displays whether the lock sensor is on or off (even if the sensor is touched and contact is maintained, "ON" is displayed only momentarily). Use this Data List item to help determine if there is an lock sensor malfunction when the entry lock function does not operate.

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

D-Door Touch Sensor

Driver door touch sensor (unlock sensor) / ON or OFF

ON: Driver door touch sensor (unlock sensor) touched

OFF: Driver door touch sensor (unlock sensor) not touched

Displays whether the unlock sensor is on or off (even if the sensor is touched and contact is maintained, "ON" is displayed only momentarily).
Use this Data List item to help determine if there is an unlock sensor malfunction when the entry unlock function does not operate.

D-Door Trigger Switch

Driver door touch sensor (lock sensor) / ON or OFF

ON: Driver door touch sensor (lock sensor) touched

OFF: Driver door touch sensor (lock sensor) not touched

Displays whether the lock sensor is on or off (even if the sensor is touched and contact is maintained, "ON" is displayed only momentarily).
Use this Data List item to help determine if there is an lock sensor malfunction when the entry lock function does not operate.

HINT:

When checking the operation of the entry lock function several times, it can be operated up to 2 times consecutively. To operate the function 3 times or more consecutively, the doors need to be unlocked once. However, this is only for the entry lock function, other door lock operations, such as a wireless door lock operation can be performed consecutively.

OK:

The Techstream display changes correctly in response to the operation of the front door outside handle assembly LH.

GO TO STEP 6

5.	CHECK KEY DIAGNOSTIC MODE

(a) Check the following antenna in key diagnostic mode (See page (b) Select either channel 1 or channel 2 and perform key diagnostic mode inspection ).

(b) Select either channel 1 or channel 2 and perform key diagnostic mode inspection for each channel.

(1) Check the electrical key antenna (for driver door):

When the electrical key transmitter sub-assembly is brought within 0.7 to 1 m (2.30 to 3.28 ft.) of the front door outside handle assembly LH, check that the wireless buzzer sounds.

Text in Illustration

*a	0.7 to 1 m (2.30 to 3.28 ft.)

HINT:

Select either channel 1 or channel 2 and inspect key diagnostic mode for each channel.
If the buzzer sounds with [CH1] displayed but not with [CH2], the electrical key transmitter sub-assembly cannot be detected by channel 2 due to a malfunction, such as wave interference.

Result

Result	Proceed to
Wireless buzzer does not sound	A
Wireless buzzer sounds	B

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

6.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - FRONT DOOR OUTSIDE HANDLE ASSEMBLY LH)

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

(b) Disconnect the F40 front door outside handle assembly LH connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
C29-4 (CLG1) - F40-6 (ANT1)	Always	Below 1 Ω
C29-3 (CG1B) - F40-4 (ANT2)	Always	Below 1 Ω
C29-4 (CLG1) or F40-6 (ANT1) - Body ground	Always	10 kΩ or higher
C29-3 (CG1B) or F40-4 (ANT2) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.	CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO DRIVER DOOR ELECTRICAL KEY ANTENNA)

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

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

OK:

Tester Connection	Switch Condition	Tool Setting	Specified Condition
F40-6 (ANT1) - F40-4 (ANT2)	Procedure: Engine switch off All doors closed Electrical key transmitter sub-assembly not inside vehicle All doors locked through wireless operation (electrical key transmitter sub-assembly brought outside detection area*)	5 V/DIV., 100 ms/DIV.	Pulse generation (See waveform 1)

Tester Connection

Switch Condition

Tool Setting

Specified Condition

F40-6 (ANT1) - F40-4 (ANT2)

Procedure:

Engine switch off
All doors closed
Electrical key transmitter sub-assembly not inside vehicle
All doors locked through wireless operation (electrical key transmitter sub-assembly brought outside detection area*)

5 V/DIV., 100 ms/DIV.

Pulse generation

(See waveform 1)

*: For details about the entry function detection area, refer to Operation Check (See page ).

Text in Illustration

Front view of wire harness connector

(to Front Door Outside handle assembly LH)

Waveform 1

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

8.	CHECK ENTRY LOCK OPERATION

(a) Connect all connectors and check that the entry lock and unlock functions operate (See page Result ).

Result

Result	Proceed to
Entry function does not operate normally	A
Entry function operates normally	B

END (CONNECTOR WAS NOT CONNECTED SECURELY)

9.	REPLACE FRONT DOOR OUTSIDE HANDLE ASSEMBLY LH

(a) Temporarily replace the front door outside handle assembly LH with a new or known good one (See page ).

10.	CHECK ENTRY LOCK OPERATION

(a) Check that the entry lock and unlock functions operate (See page Result ).

Result

Result	Proceed to
Entry function operates normally	A
Entry function does not operate normally	B

END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY LH WAS DEFECTIVE)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

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