DESCRIPTION If the alarm function of the theft deterrent system operates unintentionally, one of the following may be the cause.
- Short to ground in any door courtesy light switch circuit or the engine hood courtesy switch (hood lock assembly) circuit.
- Unstable main body ECU (multiplex network body ECU) power source voltage.
HINT: Preconditions for arming preparation:
- Make sure the engine switch is off, all the doors and the hood are
closed and all the doors have been locked by wireless operation or entry
operation.
WIRING DIAGRAM
 CAUTION / NOTICE / HINT
NOTICE:
- Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here 
- The theft deterrent system uses the CAN communication system. Inspect
the communication function by following How to Proceed with
Troubleshooting. Troubleshoot the theft deterrent system after
confirming that the communication system is functioning properly.
Click here
- The following troubleshooting procedure is based on the assumption that
systems related to the theft deterrent system are normal. Confirm that
the systems related to the theft deterrent system are not malfunctioning
before performing the following procedure.
Click here
- If the vehicle or vehicle controls are operated (for example, during
initial inspection when the vehicle is brought in for repair) before
operation history has been read and saved, the operation history
information could be lost.
- The operation history function uses the current system time of the
Techstream and the time counter inside the controlling ECU to calculate
the times shown in the operation history. For this reason, before
reading the operation history, first make sure that the Techstream
system clock is accurately set to the current time.
PROCEDURE |
1. | CHECK THEFT DETERRENT SYSTEM OPERATION HISTORY |
(a)
Use the Techstream to check the theft deterrent system operation
history around the time the customer reported the malfunction to have
occurred. Click here (1)
Check if there is operation history around the time that the customer
reported the malfunction to have occurred, and perform an operation
check. |
Result | Proceed to | |
There
is operation history around the time that the customer reported the
malfunction to have occurred, but a malfunction could not be identified
during the operation check. | A | |
There
is operation history around the time that the customer reported the
malfunction to have occurred, and the malfunction was identified during
the operation check. | B | |
There is no operation history around the time that the customer reported the malfunction to have occurred. |
C |
| B |
 | GO TO STEP 7 |
| C |
| END |
|
A |
 | |
| 2. |
CHECK SECURITY INDICATOR LIGHT OPERATION |
(a) Check that the security indicator light is illuminated when the theft deterrent system is in the arming preparation state.
Click here (b) Check that the security indicator light blinks when the theft deterrent system is in the arming state.
Click here |
State of Theft Deterrent System |
Contents | Security Indicator Light Condition | |
Disarmed state (1), (2) |
Theft deterrent system is unset. |
- Off (Immobiliser system unset)
- Blinking (Immobiliser system set)
| | Arming preparation state |
Standby
period after theft deterrent system set conditions are met but before
theft deterrent system is actually set (approximately 30 seconds). (Theft detection not possible) |
On | | Armed state |
Theft deterrent system is set. (Theft detection is possible) |
Blinking (Immobiliser system set) | |
Alarm sounding state | Theft attempt is detected, and alarm operates using turn signal lights, security horn assembly and vehicle horns.
(Alarm sounds for 57 seconds) |
On |
| NG |
| GO TO OTHER PROBLEM |
|
OK | |
| |
| 3. |
READ VALUE USING TECHSTREAM (Hood Courtesy SW) |
(a) Connect the Techstream to the DLC3. (b) Turn the engine switch on (IG).
(c) Turn the Techstream on. (d) Enter the following menus: Body Electrical / Main Body / Data List.
(e) Read the Data List according to the display on the Techstream. Body Electrical > Main Body > Data List
|
Tester Display | Measurement Item |
Range | Normal Condition |
Diagnostic Note | |
Hood Courtesy SW | Engine hood courtesy switch |
OFF or ON | OFF: Engine hood closed
ON: Engine hood open |
- | Body Electrical > Main Body > Data List
|
Tester Display | | Hood Courtesy SW |
OK: The Techstream display changes correctly in response to the engine hood courtesy switch (hood lock assembly) status.
| NG |
| GO TO STEP 5 |
|
OK | |
| |
| 4. |
INTERVIEW THE CUSTOMER | (a)
If the problem symptoms could not be reproduced, explain to the
customer the details of the operation history, such as the input signal
timings of the key, etc. Click here
OK: Cause was identified
| OK | |
END |
| NG |
| CHECK FOR INTERMITTENT PROBLEMS |
| 5. |
INSPECT ENGINE HOOD COURTESY SWITCH (HOOD LOCK ASSEMBLY) |
(a) Remove the hood lock assembly. Click here
(b) Inspect the engine hood courtesy switch (hood lock assembly).
Click here
| NG |
| REPLACE HOOD LOCK ASSEMBLY |
|
OK | |
| |
| 6. |
CHECK
HARNESS AND CONNECTOR (ENGINE HOOD COURTESY SWITCH (HOOD LOCK ASSEMBLY)
- MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND BODY GROUND) |
(a) Disconnect the A12 engine hood courtesy switch (hood lock assembly) connector.
(b) Disconnect the G33 main body ECU (multiplex network body ECU) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
G33-30 (HCTY) - A12-2 (+) |
Always | Below 1 Ω | |
G33-30 (HCTY) or A12-2 (+) - Other terminals and body ground |
Always | 10 kΩ or higher | |
A12-1 (E) - Body ground |
Always | Below 1 Ω |
| OK |
| REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
| 7. |
INTERVIEW THE CUSTOMER | (a)
If the problem symptoms could not be reproduced, explain to the
customer the details of the operation history, such as the input signal
timings of the key, etc. Click here
OK: Cause was identified
| OK | |
END |
| NG |
| CHECK FOR INTERMITTENT PROBLEMS | | 
