360 Alarm LED

On my car the alarm LED is always on solid after starting the car. Is this the normal operation?

Thanks, John

Does the siren chirp when you lock/unlock the car? If not then the siren assy. is bad. You can disconnect it and remove it without loosing any functions except the siren chirp. Mine, in a 355, has been out for a year now cause it costs over $500.
Everything else works fine except the light is always on.

Dave,

I don't think my car chirps when working properly. I do think that it has a backup battery in the siern assy. I am going to remove the siren and see if I can get it apart and replace the battery.

Yes, it has two small lithium ion batteries, however the case is a sealed plastic unit. You have to saw it apart, and getting batteries might be a problem. On mine the circuit board was burnt due to corrosion caused by water getting inside. Bad design on the connectors. They should be waterproof, but they are not.
As far as I can determine the only thing it does is chirp and turn out the LED.

Dave,

Thanks for the info. Did you repair yours or buy a new one?

John

Neither, doing without for the time being. No ill effects yet.

I removed the siren and replace the nicad batteries with 2 generic 3.6V nicads wired in series and the LED is off. I had to cut the front of the siren off with a dremmel tool, the nicads inside are a 2 German only 3.6v nicads.

Hi John,

EXCELLENT TIP !!!

Glad you resolved the problem. And thank you very much for the follow up. If you don't mind I'd like to put your problem & fix in the permanent Tech Archives.

Best Regards, JRV

That was brave! Same thing happened on my 360 and it seems to be common. It also happened on my 456, which has the same alarm system I'm told. In both cases it was fixed by replacing the backup battery, under warranty. The actual cost is about $200 I think. In my case there was a downside to not getting it fixed, in that the alarm is connected to a satellite tracking device (TrakBak). This meant that every time I reversed out of the garage I got a call from their control centre checking if it was being stolen. It's fun, but only the first time.

[bill.jones]

I successfully replaced the alarm siren batteries with an external rechargeable battery (now mounted next to the master cylinder). The printed circuit board in the siren unit was quite badly corroded by the old on-board batteries. This cleaned up ok after considerable scrubbing with alcohol and a dunking in an ultrasonic bath.

The siren now "chirps" once when locking and twice when unlocking. Apparently the alarm LED display on the dashboard should now be out, BUT, in my car, the LED comes back on permanently after the initial alarm system check (all doors, trunk, engine hatch, etc., closed).

Any other reason that is causing the LED to be permanently on?