high pitched alarm sound under hood

[carloscanada]

just got a new to me -old 2000 LE -
opened the hood - engine cold around 2 below celsius outside - had sat for a day -
high pitch wee-woo-wee -woo noise coming from back passenger side of engine compartment?
quite loud you can hear it clearly standing in front of car with hood open
any ideas? can't seem to find any alarms - can't hear it when the hood is closed - no warning lights on dash - can't hear it when engine is runnning.......

Thanks,

I should clarify - car wasn't running - no key in it - had a new battery installed a couple days prior at the dealer
just opened the hood to check the new battery and i hear the whistling dee-doo dee doo...alternating frequencies

[carloscanada]

Upon closer inspection it is a 'counter-attack electronic rust control' box with a beeping red light and making the alarm noise. I'll see if i should disconnect it or if it will kill the battery -
anyone know about these electronic rust thingies?

[TierOneSupplier]

I'm not familiar with the rust prevention devices but if you have any concerns about it draining your battery, I'd disconnect it. We get a lot of winter weather here and our '98 Sienna has been exposed to a lot of salt in its 284,000 miles of driving, and there's not a bit of rust on it. I doubt you need this device.

[carloscanada]

thanks tier one - I looked it up and it is claimed it uses about one d cell worth of juice and is supposed to shut off if battery is low - I guess I'll leave it on till spring and i can get it undercoated, we get mucho salt/rain/fog and very cold on a little east coast island - PEI . have some rust spots developing so I guess it couldn't hurt.
Peace.