[96darkhorse]

Hey fellas. How are you. I’m trying to see if I can figure out the following problem. My battery took a dump and when I went ahead and installed a new one, once I connect both terminals, the alarm starts going off and the trunk opens by itself. The remote does not work to turn off the alarm. I’m able to start the car but the alarm keeps going off. Anybody had this issue before? Thanks in advance

 

[nstar]

I would start over by pulling cables off battery check the short red cable for corrosion put positive on first then neg on display on dash you should get driver's window down and up pass, rear,etc.Then should start up. The trunk and alarm is something a low voltage battery might do you might want to put charger on your new battery for a while. Here is link to installing XTS battery.
BATTERY CHANGE! 2015 Cadillac XTS - Bing video

 

[Excalibur]

Hey fellas. How are you. I’m trying to see if I can figure out the following problem. My battery took a dump and when I went ahead and installed a new one, once I connect both terminals, the alarm starts going off and the trunk opens by itself. The remote does not work to turn off the alarm. I’m able to start the car but the alarm keeps going off. Anybody had this issue before? Thanks in advance

Welcome to CF! One post in almost 9.5 years...I think you get the lurker award, lol. I suggest you update the vehicle listed under your username to reflect your current ride and year.

A quick internet search came up with the following - worth a try.

To reset the the anti-theft system - three ways:

• replace key fob battery, then unlock and lock the car using the fob
• unlock the car manually, using a physical key instead of a fob.
• With doors locked, disconnect the negative cable, wait ten minutes and then reconnect

Best of luck!

 

[Tripwire]

YES lurker award.....perhaps this is a chance as a custom title? until of course there is even a woorse offender?

 

[rayban1]

I just changed my battery today and it was doing the same , alarm or horn going off. I had to remove the negative battery terminal about three times after connecting and than it stopped and I was able to do the window up and down reset procedure. I was on the original battery since 2014 and it just was completely dead with no warning, Went with a AC Delco 48S from auto zone and all is good.