Toyota Tacoma (2015-2018) Service Manual: All Door Entry Lock/Unlock Functions do not Operate, but Wireless Functions Operate

Toyota Tacoma (2015-2018) Service Manual / Door Lock / Smart Key System(for Entry Function) / All Door Entry Lock/Unlock Functions do not Operate, but Wireless Functions Operate

DESCRIPTION

When the wireless operation can be used to lock and unlock the doors, communication between the electrical key and TPMS receiver assembly and certification ECU (smart key ECU assembly) is normal. If the entry lock and unlock functions do not operate, the entry cancel function may be set through the customize function, there may be communication problems between the electrical key transmitter sub-assembly and vehicle, or there may be wave interference.

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 WAVE ENVIRONMENT

(a) Move the electrical key transmitter sub-assembly as described below and perform the operation inspection.

HINT:

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.
The transmitting wave of the wireless function and entry function are the same, but the wave logic is different. As a result, it is possible that only the wireless function or only the entry function is affected by wave interference.

(1) Bring the electrical key transmitter sub-assembly approximately 0.3 m (0.984 ft.) from the front door outside handle assembly LH and perform a driver door entry lock and unlock operation check.

HINT:

Communication may not be possible if the electrical key transmitter sub-assembly is within 0.2 m (0.656 ft.) of the rear bumper.

Text in Illustration

*a	Approximately 0.3 m (0.984 ft.)

Result

Result	Proceed to
All operation checks fail	A
All operation checks are normal	B
Some operation checks are normal	C

AFFECTED BY WAVE INTERFERENCE

GO TO OTHER PROBLEM

3.	CHECK KEY DIAGNOSTIC MODE

(a) Check the following antennas 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.

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.

OK:

Wireless buzzer sounds.

Text in Illustration

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

Result

Result	Proceed to
All diagnostic mode inspections fail	A
Some diagnostic mode inspections fail (door)	B
All diagnostic mode inspections are normal	C

GO TO OTHER PROBLEM

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

4.	CHECK ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY

(a) Check if there is another electrical key transmitter sub-assembly available that is already registered to the vehicle.

Result

Result	Proceed to
Another registered electrical key transmitter sub-assembly is not available	A
Another registered electrical key transmitter sub-assembly is available	B

GO TO STEP 6

5.	ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY REGISTRATION (NEW ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY)

(a) Register a new electrical key transmitter sub-assembly (See page ).

6.	CHECK ENTRY LOCK OPERATION

(a) Using another registered electrical key transmitter sub-assembly, 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 (ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY WAS DEFECTIVE)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

Open in Rear Floor Electrical Key Oscillator Circuit (B27A6)

DESCRIPTION The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 2 indoor electrical key antenna assembly (rear floor). For the No. 2 indo ...

Open in Front Floor Electrical Key Oscillator Circuit (B27A5)

DESCRIPTION The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 1 indoor electrical key antenna assembly (front floor). For the No. 1 ind ...

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