2 PCS Car Key Test Coil, Auto Key Lock Chip Induction Signal Diagnostic Test Card, Automotive Anti-Theft System Auto-Sensing Signal Quick Test Tool, Car Accessories

Worked as they should, price was great, all you need to do is hold it over the cylinder and insert the key. super easy! fast shipping from seller.

This tool is super simple and does its job very well. I think they sell it in a 2-pack to keep shipping costs below half the price. If you're having troubles with a transponder key, this may help you diagnose whether its the key or the car. Every mechanic should have one of these in with their OBD-II reader.

This device is small, easy to store. It requires a flat surface around the key switch to have this in place while you turn the key. On my mustang I was able to get it to work (on a car that had no issues), and as I turned the key from off to "on" I got two little flashes from the light. At forst I thought this was intended to check the signal from the transponder key, but it seems to measure the interaction between the key and the security system.

I have been having trouble with the anti-theft on my 2007 Honda CRV triggering when it shouldn't. I thought I would give this a try to see if it would help troubleshoot the problem. Excellent choice. This tool is well made out of good quality materials. Fit and finish are good. Works well. It let me see that the anti-theft wasn't transmitting to the key all the time, so it would appear that there is an intermittent problem with it. Saved me many hours of trying to figure out the problem. Highly recommend. 5 stars.