ORO Technology W410-A Complete Retrofit TPMS Kit for Passenger Car or Light Truck

This was a great unit when it was working. The system would learn the position of each of the four tire sensors and displayed the correct tire pressure ±1psi of the actual pressure. The battery voltage display was always high, consistently 0.4V to 0.5V higher than the actual voltage measured with two calibrated multimeters. This was a surprise as building an accurate voltmeter is something even a high school student can do.However, after three months, the tire pressure for one front tire was always 13% higher than the actual pressure and for a rear tire always 5% lower. Slowly the rest of the sensors started to lose accuracy. I measured tire pressures using my trustworthy Longacre Racing Tire Gauge ( https://www.amazon.com/gp/product/B00TO672OI/ ) which is rated at 2% accuracy but IRL delivers 0.5% accuracy. I emailed ORO Technology who told me 1) their unit is always right and my tire gauge and multimeters are all wrong, and 2) to calibrate the tire sensors I need to send the sensors to Infineon and NXP, which is insulting and ridiculous.Despite numerous emails ORO Technology refused to admit this unit is defective and useless, despite hilarious evidence that the unit is bad. In this was they denied me a warranty claim. I'm out $295 for an overpriced inaccurate voltmeter.

Everything works great, as long as the tire installer does not break the sensor when installing it. Currently I am waiting to hear from ORO if I can get a replacement sensor (the broken one plus an extra set of four would be great).I left them a message to see if I can get a replacement.....if I can great, five star it is.......if not.......well that's not good and I will lower the star level.If I were their engineer (I am such an engineer), I would look at over-moulding the connection of the stem to sensor with a metal reinforcement. Being just plastic I can see this being a problem as mine is, and long term too with the stress of heat cycles and forces it will see during its lifetime.The display is clear and easy to read, setting up what it displays is just as easy.My power adapter in my car is constant on, this leaves the display on all the time. They might want to look at a way to turn off the display when the car is not in use (sense vibration maybe).Later on (if I can get the replacement sensor) I will look at hooking it up to a switched power circuit in my car so it will turn off and one with the car. It would be a good addition to the kit to have connections for both ways included.So my overall rating is in limbo, hopefully I will get replacement sensors and can give it 5 stars.By the way, I am not looking for free replacement sensors, it is obviously installer error and could have been avoided if he took more care doing the work.