Toyota Tacoma (2015-2018) Service Manual: Driver Side Door Entry Unlock Function does not Operate

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

DESCRIPTION

If the entry unlock function does not operate for the driver door only, but the entry lock function operates, the request code is being transmitted properly from the driver door. In this case, there may be a problem related to the touch sensor (connection between the certification ECU (smart key ECU assembly) and front door outside handle assembly LH [unlock sensor]).

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.	READ VALUE USING TECHSTREAM (FL DOOR LOCK POS)

(a) Connect the Techstream to the DLC3.

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

(d) Enter the following menus: Body Electrical / Main Body / Data List.

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

Main Body

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
FL Door Lock Pos	Front door LH unlock detection switch signal / UNLOCK or LOCK	UNLOCK: Front door LH unlocked LOCK: Front door LH locked	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

FL Door Lock Pos

Front door LH unlock detection switch signal / UNLOCK or LOCK

UNLOCK: Front door LH unlocked

LOCK: Front door LH locked

OK:

The Techstream display changes correctly in response to the lock/unlock operation of the front LH door.

GO TO LIGHTING SYSTEM (Proceed to Door Unlock Detection Switch Circuit)

3.	READ VALUE USING TECHSTREAM (D-DOOR TOUCH SENSOR)

(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.

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.

OK:

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

Result

Result	Proceed to
NG	A
OK	B

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

4.	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

(d) Reconnect the F40 front door outside handle assembly LH connector.

(e) Reconnect the C29 certification ECU (smart key ECU assembly) connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	CHECK FRONT DOOR OUTSIDE HANDLE ASSEMBLY LH (INPUT TO DRIVER DOOR UNLOCK SENSOR)

(a) Using an oscilloscope, check the waveform.

Text in Illustration

Component with harness connected

(Certification ECU (smart key ECU assembly))

Waveform 1

Unlock sensor not touched

Unlock sensor touched

OK:

Tester Connection	Switch Condition	Tool Setting	Specified Condition
C29-4 (CLG1) - C29-11 (E)	Procedure: Engine switch off Electrical key transmitter sub-assembly brought outside vehicle All doors locked Electrical key transmitter sub-assembly not near the vehicle Driver door unlock sensor touched	5 V/DIV., 40 ms/DIV.	Pulse generation (See waveform 1)

Tester Connection

Switch Condition

Tool Setting

Specified Condition

C29-4 (CLG1) - C29-11 (E)

Procedure:

Engine switch off
Electrical key transmitter sub-assembly brought outside vehicle
All doors locked
Electrical key transmitter sub-assembly not near the vehicle
Driver door unlock sensor touched

5 V/DIV., 40 ms/DIV.

Pulse generation

(See waveform 1)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

REPLACE FRONT DOOR OUTSIDE HANDLE ASSEMBLY LH

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 ass ...

Driver Side Door Entry Lock Function does not Operate

DESCRIPTION If the entry lock function does not operate for the driver door only, but the entry unlock function operates, the request code is being transmitted properly from the driver door. In t ...

Other materials:

ECU Power Source Circuit
WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this system before performing the following inspection procedure. PROCEDURE 1. INSPECT BATTERY (a) Check the battery voltage. Standard voltage: 11 to 14 V NG ...

Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART TOUCH SELECT 2-4 AND HIGH-LOW SYSTEM DTC Code Detection Item See page P163B 4WD ECU Malfunction P17A0 Automatic Disconnecting Differential Motor Control Circuit Open ...

Low Power Supply Voltage Malfunction (C1241)
DESCRIPTION If there is a problem with the skid control ECU (master cylinder solenoid) power supply circuit, the skid control ECU outputs the DTC and prohibits operation under the fail-safe function. If the voltage supplied to terminal IG1 is not within the DTC detection threshold due to mal ...