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2012 Ford Mustang - is aftermarket alarm setting off tire sensor light?

Bought a 2012 Mustang Coupe from a dealership August 2018. Car came with after-market tires and sensors. Had after-market alarm installed. Recently, tire sensor light on dash came on. Went to dealership and they blamed alarm folks for light going on and washed their hands of issue. Went to alarm installer and they said one has nothing to do with other.
Although I had the tire sensors checked and trained with different mechanics, the tire light initially turns off then goes back on soon after. Checked tires and didn’t find any nails. Each mechanic has said sensors are good.
What could be turning tire light back on?
PS: I was told although sensor lights indicate they are ok, they could still be bad? Is this true?

I have aftermarket sensors in my 2013 Mustang. They work, no problems. It is possible that one of your sensors’ batteries are weak and not producing a strong enough signal for the car to read but strong enough for the mechanics to read.

It is also VERY possible that your alarm system has so much electromagnetic radiation it wipes out one or more sensor’s signal. This is caused from poor electrical design of the alarm system. Generally these systems cause more harm than good and this very well may be one of those times.

See if it is possible to remove power from the alarm system and still start the car. If it is, kill the alarm for a week and see if the tire pressure warning cures itself. If it does, it is the alarm causing the problem. If it doesn’t one of the sensors likely needs to be replaced.

Thank you for your response. We happened to disconnect the “Viper” alarm last Friday and are having the car diagnostically checked today. We’ll see what happens. I will discuss your response with mechanic.

Ed