Alarm system going off? Reset?

Hello,

Try this guide

https://www.2carpros.com/articles/how-to-reset-a-security-system

If not it sounds like the certification ECU maybe going out but lets disconnect the battery and remove the certification ECU to check for corrosion also this can sometimes fix bad connections. I have also seen where the drivers side front door latch wears and it causes the micro switch inside to not work right causing the alarm to do off. With the car locked and the alarm on try pulling on each one of the doors (shut) to see if you can get the alarm to go off this will tell you which door latch to replace. Here are the wiring diagrams for the security system so you can see how it works and the location of the certification ECU. Check out the diagrams (below). Please let us know what happens.

It sounds like you have a bad connection at the battery even if the security was on it would not cut power to the radio. Please confirm the battery terminal connections here is a guide.

https://www.2carpros.com/articles/everything-goes-dead-when-engine-is-cranked

If they check out here is what the book says to reset the alarm system.

REGISTRATION
1. DESCRIPTION OF CODE REGISTRATION
HINT
ID codes are the same as recognition codes for the wireless transmitter and the engine
immobilizer function. Registering an ID code enables the smart access system with pushbutton
start, the wireless door lock control function ant) the engine immobilizer function
to be operated.

Code registration is needed when the certification ECU, ID code box, steering lock ECU
or key is replaced with a new one.

PROCEDURES
The vehicle with the smart access system with push-button start system does not have a key slot. Therefore, hold the key close to the engine switch to register the key, as shown in the illustration below.

Fig. 3: Identifying Engine Switch Register Key

2. PART REPLACEMENT KEY REGISTRATION
The following table shows ECU replacement and key registration procedures in case the malfunctioning ECU has been identified after troubleshooting the smart access system with push button start.

HINT:
The following procedures indicated in the table below require the use of the intelligent
tester:

A maximum of 7 keys can be registered.
PART REPLACEMENT KEY REGISTRATION
Part to be replaced Condition Procedure Reference

1. Replace certification ECU - ENGINE IMMOBILIZER (EXCEPT HYBRID)

2. Re Register all keys (new key ID registration)
PROCEDURE "B" See step b Some keys are lost Key ID codes can be registered and erased

1. Erase key codes (key ID erasure) PROCEDURE "D" See step d

2. Perform additional key registration procedure (additional key ID registration)

PROCEDURE "C" See step c
3. Replace certification ECU -
4. Re Register all keys (new key ID registration)

HINT: If some keys are not registered during above steps, they will be disabled because they cannot be registered later

ENGINE IMMOBILIZER (EXCEPT HYBRID)

Part to be replaced Condition Procedure Reference

All keys are lost
1. Replace ID code box -
2. Replace certification ECU -
3. Re Register all keys (new key ID registration)

HINT: If some keys are not registered during above steps, they will be disabled because they cannot be registered later

Key Customer has brought at least 1 key
1. Using remaining key, erase lost key code (key ID erasure)

a. PROCEDURE "A"

1. Connect intelligent tester (with CAN VIM) to DLC3
2. Turn engine switch on (IG) Select "SMART ACCESS / ID UTILITY / SMART CODE REG" from tester menu
3. HINT:The engine switch cannot be turned on (IG) more than 10
times. After connecting tester, turn tester on while turning driver's
side door courtesy light switch on and off repeatedly at 1.5-second
intervals or less to continue key registration procedure
2. Confirmation of ECU code
Perform operation according to prompts on tester screen
HINT: The mode is automatically selected by tester, new registration mode
or add mode Hold unregistered key close to engine switch (For details, refer to
PROCEDURE "1" ) ENGINE IMMOBILIZER (EXCEPT HYBRID) -2007 Toyota Camry XLE
Confirm that wireless door lock buzzer sounds. Place unregistered key on front passenger's side seat Confirm that wireless door lock buzzer sounds
4. Registration of
ID code Perform operation according to prompts on tester screen
5. End of registration Finish new key ID code registration
(1) Repeat this process for each key which is to be registered for the vehicle. Finish the
procedure for each key within 30 seconds. If the procedure for any of the keys has
not been finished within the specified time, perform registration procedures from
process 1 again. Make sure that only 1 key is in the cabin during registration
procedures. If 2 or more keys are in the cabin simultaneously, electric waves will
interfere with each other, preventing normal registration.
b. PROCEDURE "B"
New key ID registration (when replacing certification ECU)
KEY REGISTRATION PROCEDURE "B" REFERENCE
Process Procedure
1. Start of registration
1. Connect Intelligent tester (with CAN VIM) to DLC3
2. Turn engine switch on (IG)
Select "SMART ACCESS / ID UTILITY / SMART CODE
REG" from tester menu
3. HINT:The engine switch cannot be turned on (IG) more than 10
times. After connecting tester, turn tester on while turning driver's
side door courtesy light switch on and off repeatedly at 1.5-second
intervals or less to continue key registration procedure
2. Confirmation of ECU code
Perform operation according to prompts on tester screen
HINT: The mode is automatically selected by tester, new registration
mode or add mode
3. Confirmation of all registered keys
(1) Hold unregistered key close to engine switch (For details, refer to
PROCEDURE "1" )
Confirm that wireless door lock buzzer sounds
4. Confirmation of ECU code Perform operation according to prompts on tester screen
5. Verification of unregistered key (1)
Hold unregistered key close to engine switch (For details, refer to
PROCEDURE "1" )
Confirm that wireless door lock buzzer sounds. Place unregistered
key on front passenger side seat
Confirm that wireless door lock buzzer sounds
5. Registration of ID code Perform operation according to prompts on tester screen

This guide can help as well

https://www.2carpros.com/articles/how-to-reset-a-security-system

Please run down this guide and report back

Cheers

Hi helplessone,

From the symptom description, either the battery is weak or the terminals had not been secured well.

Are you still getting the same problem now?

If that is the case, you would have to check the starter motor. It could be weak.

It could possibly be an intermittently failing igntion switch. When this happens, power supply is interrupted resulting in the alarm system being tripped.

Hi there,

Trying to diagnose this type of "after market " item is near impossible with out being able to see first hand how it is wired up. I would get an auto electrician to disarm the system, then either install a know new unit that you will be able to repair if it goes wrong.

Mark (mhpautos)

I the ignition switch is failing, the problem is going to get worse and might even cause engine to stall and/or prevent it from starting more often.