[Bck]

I’ve had my vehicle at the dealership twice to check and then fix the reason why my alarm continues to randomly go off. The first time they said it was the hood switch. So I got that fixed. Within a week my alarm started going off randomly again. Took it back to the dealership and now they said it’s the rear door latch sending an intermittent open signal causing alarm false trigger. I paid to now get that done. After the dealership having my vehicle for exactly two weeks. I go pick my vehicle up today. Come back home, locked it, and within the hour my alarm went off. It’s a 2012 RR HSE, with a little over 95 thousand miles. This all started after the dealership changed my battery and put in a new one. I thought if anyone can figure out why my alarm randomly goes off, I would think the dealership technician would know. Can anyone share any ideas or info they may have?

 

[V50_M66]

Sounds like your alarm module might be on its way out. I currently have the same problem with my Volvo - the alarm will go off randomly, with the fault being traced back to random doors. The little battery that's on the circuit board only lasts 7-10 years before it starts to die and/or leak, and when this happens, it can cause all sorts of alarm related issues, usually resulting in the alarm going off randomly.

 

[reverendALC]

Does this issue happen anywhere? Or only at home?

I used to install car alarms professionally, and several times I had to shroud alarm brains in aluminum foil because of environmental factors... once for a fella who lived next to a substation, once for a fella who’s workplace set it off, and once for a guy who drove past a facility on his way to work.

not sure what caused it, but entirely sure a wrap or two with foil on the alarm unit solved it. Considering these rigs don’t have a dedicated “security” ECU, I’m not sure where you’d possibly start or if there’s a similar solution, but... true stories

 

[Bck]

It started when I took my vehicle to the dealership and they said it’s was the hood switch that was triggering a false alarm. After the dealership replaced the hood switch my alarm still continued to randomly go off. I took it back then they said it was the rear door latch that was causing the false alarm trigger. And in that span of time my battery went dead. All these issues started after the dealership changed out my old battery and installed a new one. After having my vehicle for exactly two weeks they said they fixed the issue that was causing my battery to drain power and the alarm issue. The day I picked up my vehicle and within the hour my alarm went off. And two days later I have no power. The exact same issue I brought it to the dealership in the first place.

 

[reverendALC]

Dealerships are lame. You’ll want to find a skilled auto electric shop. They will specialize in electrical gremlins and do more faster than any dealer or general repair shop. They are hard to find though.