DESCRIPTION
If no warnings operate or the system can be set even though the conditions to set the system are not met, the main body ECU (multiplex network body ECU) cannot perform recognition due to a cutoff of the ON signal from the courtesy light switch from the doors, engine hood or back door, or some other problem.
If the automatic alarm operates when it should not operate, it may be due to a false detection by the intrusion sensor (theft warning ultrasonic sensor) or due to the ON signal being input when there is a short circuit in the courtesy light switch of the doors, engine hood or back door, or some other problem which would cause this to happen.
Tech Tips
In the following situations, the intrusion sensor (theft warning ultrasonic sensor) may operate and cause the automatic alarm system to operate even when the sensor is normal.
The driver steps away from the vehicle while other people, pets, etc. are in the vehicle.
There are things which move easily inside the vehicle, such as things hanging inside the vehicle or clothing hanging from the coat hooks.
A window or the sliding roof is open.
The vehicle is parked in a place with a lot of vibration or noise such as a parking garage.
The vehicle is being washed using a high-pressure spray gun or an automatic car washing machine.
The vehicle is continuously being struck or is vibrating due to hail or lightning.
The vehicle is continuously being subjected to impacts or is vibrating when snow or ice is being removed from the vehicle.
A frost prevention sheet which has an aluminum film is moved by wind, etc.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following procedure.
If the main body ECU (multiplex network body ECU) is replaced, refer to the Service Bulletin.
As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-Vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.*
*: w/ Door Control Battery
PROCEDURE
READ VALUE USING GTS (INTRUSION SENSOR, INTRUSION SENSOR SOUND DETECT)
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Enter the following menus: Body Electrical / Main Body / Data List.
Read the Data List according to the display on the GTS.
Tech Tips
When performing the above inspection, have the electrical key transmitter sub-assembly in the vehicle exterior detection area to perform certification (this prevents the alarm from sounding).
Note
Make sure that all windows are closed.
Make a metal-on-metal striking sound (such as by shaking keys) near the intrusion sensor (theft warning ultrasonic sensor) and check the Data List.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| Intrusion Sensor Sound Detect | Sound detection status of the intrusion sensor (theft warning ultrasonic sensor)*1*2 | ON or OFF | ON: Sound detected OFF: Sound not detected |
Only displays "ON" on the Data List once. When checking again, disconnect and reconnect the GTS. |
| Tester Display |
|---|
| Intrusion Sensor Sound Detect |
*1: w/o Door Ajar Warning Buzzer Function
Note
*2: Perform the intrusion sensor (theft warning ultrasonic sensor) operation inspection with the GTS disconnected.
From inside the vehicle, put your hand in front of the intrusion sensor (theft warning ultrasonic sensor) and move it back and forth a distance of 0.3 m (0.984 ft.) and check the Data List.
| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| Intrusion Sensor | Detection status of the intrusion sensor (theft warning ultrasonic sensor) | ON or OFF | ON: Intrusion detected OFF: Intrusion not detected |
- |
| Tester Display |
|---|
| Intrusion Sensor |
| OK |
|---|
| The GTS display changes correctly in response to the detection condition of the intrusion sensor (theft warning ultrasonic sensor). |
| Result | |||
|---|---|---|---|
|
| OK |
|
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
| NG |
|
CHECK WAVEFORM (INTRUSION SENSOR [THEFT WARNING ULTRASONIC SENSOR]) (IOUT)
Using an oscilloscope, check the waveform.
| *a | Component with harness connected (Map Light Assembly) |
*b | IOUT Initial Signal |
| *c | IOUT Initial Response | *d | Approximately 1.0 seconds |
| *e | Initial Diagnosis | *f | Approximately 1.0 to 1.6 seconds |
| *g | Approximately 0.05 seconds | *h | Approximately 5.5 seconds |
| *i | Disarmed State | *j | Arming Preparation State |
| Item | Content |
|---|---|
| Tester Connection | T6-6 (IOUT) - Body ground |
| Tool Setting | 2 V/DIV., 100 ms./DIV. |
| Condition | Theft deterrent system is set (system changes from disarmed state to arming preparation state) |
Tech Tips
If the intrusion sensor (theft warning ultrasonic sensor) is normal, an initial response is output in response to the HI input from the main body ECU (multiplex network body ECU).
If the waveform output remains LO, there may be a problem with the main body ECU (multiplex network body ECU), as there is no input from the main body ECU (multiplex network body ECU).
| OK |
|---|
| The waveform displays properly (HI is 6.5 V or higher and LO is below 1 V). |
| Result | ||||
|---|---|---|---|---|
|
| NG (for LHD) |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
| NG (for RHD) |
|
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - MAP LIGHT ASSEMBLY)
Disconnect the I47 main body ECU (multiplex network body ECU) connector.
Disconnect the T6 map light assembly connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
INSPECT MAP LIGHT ASSEMBLY
Remove the map light assembly.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE INTRUSION SENSOR (THEFT WARNING ULTRASONIC SENSOR) Click here |
| NG |
|
REPLACE MAP LIGHT ASSEMBLY Click here |