ItsJohnny

Hello, I currently own A 2010 RX 350 and have had an issue with the anti-theft system/immobilizer. The car would sometimes randomly have its alarm go off while there was nothing messing with the vehicle. The anti-theft system would engage and I would have to unlock the door with the key and press my key fob against the push-button start to start the vehicle. When the car would start I would be greeted with AFS and AWD systems disabled. Once the car got out of anti-theft mode these system lights would go away. The battery on the car is fine and it reacts the same way with both key fobs. Is there some way to disable the anti theft system and still have a working vehicle? Or are there any solutions besides bringing the car to the dealership? Thanks.

Clutchless

Is there an aftermarket remote start on it or anything else aftermarket added to the vehicle?

Try some searching using the term alarm because I think there are older posts with this issue. This forum is over 10 years old for the 3rd gen RX and almost everything you can think of has been discussed at some time.

salimshah

Clutchless makes very valid post. The issue is with "alarm" while anti theft is associated with imobilizer.

The alarm is being activated by something/breach. It can be a bad sensor. Please read up on what causes the alarm to go off. Here are few that I know off.

1. When some one uses the door release from inside the cabin after the vehicle is locked and in secure mode. [different from just being locked when RX is occupied].
2. Hood is opened when the RX is in secure mode.

Salim

afpj

How do you know the battery is fine? Load tested? Check engine bay for evidence of critters (nesting material, seeds, etc) and look at the wires. Just for kicks and grins, take the battery out of the key fobs for a while and see if the alarm still does it.

Clutchless

I think since you are in Illinois this highly recommended shop in Homer Glen, IL may be close enough and you should have them evaluate your vehicle.
​​​​​​https://tccnautomotive.com/