Why did my Lexus alarm go off when I disconnected the battery?

Why did my Lexus alarm go off when I disconnected the battery?

When they got back, both cars were completely dead. I believe the alarm system was disarmed (i.e. doors unlocked) when he popped the hood to access the battery. He then disconnected the battery and charged it for a day. The moment he connects the battery, the horn blares.

What happens when you disconnect the battery on a Lexus ES330?

For future reference be sure that when you disconnect the battery, that the alarm system has been disarmed ie doors are unlocked with remote or key. Ah. sorry for not being specific. They left an ES330 and RX300 in the garage when they went on a trip (1.5 months).

Is the battery on my 1999 Lexus RX300 dead?

I tried the search but couldn’t find anything that matches. My parents have a 1999 rx300 with a dead battery (they were gone for 40 days). The battery was disconnected and charged.

Can a battery disconnect cause an alarm issue?

Horn keeps blaring and car won’t start. The key does turn in the ignition though. Any ideas? Thanks in advance. Your not the first one to have an alarm issue after a battery disconnect. If you search over at Club Lexus you will get a lot of hits but no real solutions. My first thought would be to try another battery.

What happens if you unlock the trunk on a Lexus?

If any of the doors, the trunk or the hood is forcibly unlocked, or the battery terminal is disconnected and reconnected with the vehicle locked, the alarm will activate. The alarm blows the horn intermittently, the taillights, headlights and other exterior lights flash, and the engine will not start when it is activated.

How to reset the anti theft lock on a Lexus LS400?

The alarm blows the horn intermittently, the taillights, headlights and other exterior lights flash, and the engine will not start when it is activated. This condition will remain until you reset the alarm system.

When they got back, both cars were completely dead. I believe the alarm system was disarmed (i.e. doors unlocked) when he popped the hood to access the battery. He then disconnected the battery and charged it for a day. The moment he connects the battery, the horn blares.

If any of the doors, the trunk or the hood is forcibly unlocked, or the battery terminal is disconnected and reconnected with the vehicle locked, the alarm will activate. The alarm blows the horn intermittently, the taillights, headlights and other exterior lights flash, and the engine will not start when it is activated.

The alarm blows the horn intermittently, the taillights, headlights and other exterior lights flash, and the engine will not start when it is activated. This condition will remain until you reset the alarm system.

What should I do if my car alarm is not working?

Roll the windows up and lock the car. Let the car sit for five minutes while being more than 10 feet away then unlock the car. Do not disconnect the car battery because the alarm system has a rolling code that may get mixed up when reconnecting the battery.