Stereo & Electronics - VATS/Remote Lock Question

Been having issues with the car not turning over and the security light staying on when it won't start..also when I drive down the road the security light will come on and stay on then turn off at times.

Anyway I noticed the car use to beep twice when I locked it using the key fob, but a month or so ago it only beeped once. Not sure if this is a clue to what may be wrong. Right now I am attempting to just use a resistor to see if that will fix it. But I am thinking it may not be a key or cyclinder issue.

Also when I test the ohms of the key i get anywhere from 3.74 all the way up to 18. When the car wouldn't work I was testing the key at around 10+ ohms. I put the key in and it turns on, when I pull the key out and test it tests at 3.74 which seems like that is where it should be as that is the most consistent reading I have got while testing

You must not be checking your meter range when testing the key. The lowest value resistor used for VATS is 402 ohms. Your 3.74 is almost certainly #10 - 3740 ohms.

VATS Resistance Values


402
523
681
887
1130
1470
1870
2370
3010
3740
4750
6040
7500
9530
11800

If you are getting different readings with a multimeter then the BCM is probably having the same problem and that would cause the SECURITY light and failure to start. If you are confident that the readings aren't the result of a bad meter or meter usage technique then a new key should solve the problem.