DOOR LOCK: WIRELESS DOOR LOCK CONTROL SYSTEM: SYSTEM DESCRIPTION (2008 Sequoia)

SYSTEM DESCRIPTION

1. WIRELESS DOOR LOCK CONTROL SYSTEM

The wireless door lock control system functions to lock and unlock all the doors from a distance. The system is controlled by a hand-held transmitter which sends radio waves to the door control receiver. The main body ECU performs an ID code identification process and engages the door lock control.

2. FUNCTION OF MAIN COMPONENTS

Component	Function
Door control transmitter	Has LOCK, UNLOCK and PANIC switches. Has LOCK, UNLOCK, PANIC and POWER BACK DOOR switche*1. Transmits weak radio waves (recognition codes and function codes) to the door control receiver. Illuminates the indicator light (LED) during transmission.
Door control receiver	Receives weak radio waves (recognition codes and function codes) and outputs them as code data to the main body ECU.
Front door courtesy light switch Rear door courtesy light switch Back door courtesy light switch	Turns on when a door is opened and turns off when it is closed. Outputs door status codes (open or closed) to the main body ECU.
Unlock warning switch	Detects if the key is inserted in the ignition key cylinder or not.
Door lock position switch	Transmits the door lock positions of each door to the main body ECU.
Main body ECU	Sends wireless door lock control signals in response to the code data from the door control receiver and signals from each switch.

HINT:

*1: w/ Power Back Door System

3. SYSTEM FUNCTION

The door control transmitter has the LOCK, UNLOCK, PANIC, and POWER BACK DOOR switches. Operating these switches activates each function.

The wireless door lock control system has the following functions:

HINT:

Function

Operation

All door lock

Pressing the LOCK switch locks all doors.

All door unlock

(2-step unlock)

Pressing the UNLOCK switch twice within 3 seconds unlocks all the doors after the driver's door is unlocked.

Automatic lock

If none of the doors is opened within 60 seconds after they are unlocked by the wireless door lock control, all the doors will lock again automatically.

Panic alarm

Pressing the PANIC switch of the transmitter for longer than about 0.8 seconds causes the following alarms to activate:

Sounds the horn and security horn.
Flashes the hazard lights, headlights, and taillights.
Illuminates the front interior light (when the switch is in the DOOR position).

While the panic alarm is operating, pressing any switch of the transmitter cancels the alarm operation.

Power back door open/close operation*1

Pressing the POWER BACK DOOR switch of the transmitter for longer than about 0.8 seconds opens or closes the back door.

Answer back

When the doors are locked by wireless operation, the hazard warning lights flash once, and wireless door lock buzzer sounds once.
When the doors are unlocked by wireless operation, the hazard warning lights flash twice and wireless door lock buzzer sounds twice.
When the back door is opened by wireless operation, the hazard warning lights flash twice and power back door buzzer will sound for 0.8 seconds.*1

Door ajar warning

The buzzer sounds when the LOCK switch is pressed when any of the doors are ajar, and it sounds for 10 seconds continuously. The buzzer stops when all doors are closed or the UNLOCK switch is pressed.

Illuminated entry

When all the doors are locked, pressing UNLOCK causes the interior lights to come on simultaneously with the unlock operation.

Self-diagnostic mode

The following are ways to enter the self-diagnostic mode:

If the door control receiver receives normal radio waves from the door control transmitter when the system is in diagnostic mode, it flashes the interior light in a normal pattern that corresponds to the function of each switch.
Read DTCs with the Techstream.

Transmitter recognition code registration

Enables the registration (writing and storing) of 4 types of transmitter recognition codes in the EEPROM that is contained in the door control receiver.

HINT:

*1: w/ Power Back Door System

4. TRANSMITTER RECOGNITION CODE REGISTRATION FUNCTION

The table below shows the 4 ID registration function modes by which up to 4 different codes can be registered. The codes are electronically registered (written and stored) in the EEPROM that is contained in the door control receiver.

Mode

Function

Add mode

Adds a newly received code while preserving any previously registered codes.

This mode is used when adding a new transmitter. If the number of registered codes exceeds 6, the oldest registered code is erased first.

Rewrite mode

Erases all previously registered codes and registers only newly input codes.

Confirmation mode

Confirms how many codes are currently registered. When adding a new code, this mode is used to check how many codes already exist.

Prohibition mode

Deletes all the registered codes and disables the wireless door lock function.

This mode is used when the transmitter is lost.

5. CONDITIONS THAT WIRELESS FUNCTIONS DO NOT OPERATE

(a) Lock operation is not available when:

Any of the doors is open.
The key is inserted in the ignition key cylinder.

(b) Unlock operation is not available when:

The key is inserted in the ignition key cylinder.