Toyota Tacoma (2015-2018) Service Manual: Entry Exterior Alarm and Answer-back Buzzer do not Sound

Toyota Tacoma (2015-2018) Service Manual / Door Lock / Smart Key System(for Entry Function) / Entry Exterior Alarm and Answer-back Buzzer do not Sound

DESCRIPTION

The smart key system (for Entry Function) uses the wireless door lock buzzer to perform various vehicle exterior warnings. When the conditions of each warning are met, the certification ECU (smart key ECU assembly) sends a buzzer activation request signal to the main body ECU (multiplex network body ECU) via CAN communication and the buzzer sounds.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

The smart key system (for Entry Function) uses the LIN communication system and 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.
Before replacing the certification ECU (smart key ECU assembly) or main body ECU (multiplex network body ECU), refer to smart key system (for Entry Function) (See page ).
After repair, confirm that no DTCs are output by performing "DTC Output Confirmation Operation".

PROCEDURE

1.	CHECK CUSTOMIZE SETTING (WIRELESS BUZZER RESP)

(a) Connect the Techstream to the DLC3.

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

(d) Enter the following menus: Customize Setting / Wireless Door Lock.

Wireless Door Lock

Tester Display	Default	Description	Setting	ECU
Wireless Buzzer Resp	ON	Wireless buzzer response	OFF or ON	Main body ECU (multiplex network body ECU)

Result

Result	Proceed to
"ON" is displayed	A
"OFF" is displayed	B

PERFORM CUSTOMIZE SETTING

2.	CHECK WIRELESS DOOR LOCK CONTROL SYSTEM

(a) Check that the wireless door lock functions operate normally (See page Result ).

Result

Result	Proceed to
Wireless door lock function does not operate normally	A
Wireless door lock function operates normally	B

GO TO PROBLEM SYMPTOMS TABLE

3.	READ VALUE USING TECHSTREAM (EACH UNLOCK DETECTION SWITCH)

(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
FR Door Lock Pos	Front door RH unlock detection switch signal / UNLOCK or LOCK	UNLOCK: Front door RH unlocked LOCK: Front door RH locked	-
FL Door Lock Pos	Front door LH unlock detection switch signal / UNLOCK or LOCK	UNLOCK: Front door LH unlocked LOCK: Front door LH locked	-
RR-Door Lock Pos SW*1	Rear door RH unlock detection switch signal / ON or OFF	ON: Rear door RH or LH unlocked OFF: Rear door RH and LH locked	-
RL-Door Lock Pos SW*1	Rear door LH unlock detection switch signal / ON or OFF	ON: Rear door RH or LH unlocked OFF: Rear door RH and LH locked	-

*1: for Double Cab

OK:

The Techstream display changes correctly in response to the lock/unlock operation.

GO TO LIGHTING SYSTEM (PROCEED TO DOOR UNLOCK DETECTION SWITCH CIRCUIT)

4.	PERFORM ACTIVE TEST USING TECHSTREAM (WIRELESS BUZZER)

(a) Connect the Techstream to the DLC3.

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

(d) Enter the following menus: Body Electrical / Main Body / Active Test.

(e) Perform Active Test according to the display on the Techstream.

Main Body

Tester Display	Measurement Item	Control Range	Diagnostic Note
Wireless Buzzer	Wireless door lock buzzer	OFF/ON	-

Result

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

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

5.	INSPECT WIRELESS DOOR LOCK BUZZER

(a) Disconnect the wireless door lock buzzer connector.

(b) Perform the Active Test using the Techstream and sound the wireless door lock buzzer.

Main Body

Tester Display	Measurement Item	Control Range	Diagnostic Note
Wireless Buzzer	Wireless door lock buzzer	OFF/ON	-

Standard Voltage:

Tester Connection	Condition	Specified Condition
W3-1 - W3-2	Active Test Wireless Buzzer ON	Pulse generation (frequency: 2 kHz, high voltage: 11 to 14 V, low voltage: below 1 V)
W3-1 - W3-2	Active Test Wireless Buzzer OFF	Below 1 V

Text in Illustration

*a	Front view of wire harness connector (to Wireless Door Lock Buzzer)

REPLACE WIRELESS DOOR LOCK BUZZER

6.	CHECK HARNESS AND CONNECTOR (WIRELESS DOOR LOCK BUZZER - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND BODY GROUND)

(a) Remove the main body ECU (multiplex network body ECU) from the driver side junction block (See page (b) Reconnect the 1F driver side junction block connector. ).

(b) Reconnect the 1F driver side junction block connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
W3-1 - MB-21 (BZR)	Always	Below 1 Ω
W3-2 - Body ground	Always	Below 1 Ω
W3-1 or MB-21 (BZR) - Body ground	Always	10 kΩ or higher

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

7.	CHECK HARNESS AND CONNECTOR (WIRELESS DOOR LOCK BUZZER - DRIVER SIDE JUNCTION BLOCK)

(a) Disconnect the 1F driver side junction block connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
W3-1 - 1F-29	Always	Below 1 Ω
W3-1 or 1F-29 - Body ground	Always	10 kΩ or higher

REPLACE DRIVER SIDE JUNCTION BLOCK

REPAIR OR REPLACE HARNESS OR CONNECTOR

New Key cannot be Registered

DESCRIPTION If an electrical key transmitter could not be newly registered, wave interference or a malfunction of the certification ECU (smart key ECU assembly), electrical key transmitter sub-as ...

Transmitter Battery(w/ Smart Key System)

Replacement REPLACEMENT CAUTION / NOTICE / HINT NOTICE: Take extra care when handling these precision electronic components. PROCEDURE 1. REMOVE TRANSMITTER BATTERY (a) Push the re ...

Other materials:

Disassembly
DISASSEMBLY CAUTION / NOTICE / HINT HINT: The procedure described below is for the LH side. Use the same procedure for both the LH and RH sides, unless otherwise specified. PROCEDURE 1. REMOVE REAR SEATBACK COVER (a) Remove the 2 screws. ...

Door Courtesy Switch Circuit
DESCRIPTION The main body ECU (multiplex network Body ECU) receives a door open or closed signal from each door courtesy light switch. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Recognition code registration is necessary when replacing the main body ECU (multiplex network bo ...

Disassembly
DISASSEMBLY PROCEDURE 1. REMOVE REAR PROPELLER SHAFT BOOT CLAMP (a) Place matchmarks on the propeller shaft and sleeve yoke. Text in Illustration *1 Rear Propeller Shaft Boot Clamp *2 Rear Sliding Shaft ...