Land Rover Repair: 98 range 4.6 rh side/taillight comes on, question thanks, sidelight

Question
QUESTION: During a storm I heard my 98 range 4.6 alarm on, when I went to disarm it I noticed that the truck was running. I tried to use the key to turn off the truck but it kept running so I disconnected the battery. I ran a switch from starter to battery but occassionally my rh sidelight and rh taillight comes on, even when truck isn't running. Any ideas what could be the problem?

ANSWER: Chances are some prior owner installed a remote start system and it's gone awry.  I have never heard of a stock Rover doing what you say but those aftermarket start systems are often rigged to flash sidelights and operate the alarm along with starting the vehicle

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QUESTION: Thanks a lot! Never even considered that. Can I remove the system since I don't use it or better what would you suggest?

Answer
I'm sure it can be removed.  You will probably see the aftermarket wiring under the hood.  That's a job for a car stereo/alarm guy.  You may not be able to simply pull the wires out because they may have cut some of the original starter wiring and inserted their circuitry.  It may need to be "unwired" with a bit of care