keyless fob frequency

I was wondering if anyone knows the frequency that is used by the keyless Fobs ...I work quite a bit with problems with either the car or keyfob, id like to create a frequency reader of somesort..so if i press the keyfob, the light will light up on my detector... if it doesnt, i will know the keyfob is faulty

Usually between 413 and 433mhz, right there with maritime radar. Some years ago when Chrysler launched the Voyager in Europe ,they gave the keys to journalists at Dover Harbour with instructions to take the vehicles over to France and road test them. They didn't know that they were adjacent to the radar station controlling the English Channel, probably the most powerful civilian radar going, you know what happened next don't you.

315mhz and 433mhz are the two most popular frequencies that I've seen used in automotive keyless systems.Kevin Pierson

what would be the easiest way to construct a tester that would basically turn on a light once the frequency is read by the "reader"i.e. i press remote and the little tester reads it (it works) and the led starts to turn on and off depending on freq.

You would just need an antenna system hooked to a processor that could read in the values of the actual bit stream and calculate a frequency based on that.  You wouldn't be able to actually read the data, but you could light up an LED if the recieved data appears to be within the range of the frequency you are looking at.Kevin Pierson

Or hold an old fashioned landline telephone receiver close to the remote?

howie ll wrote: Or hold an old fashioned landline telephone receiver close to the remote?

this seems like th easiest way..how would this work?

Pick up fixed landline phone, not cordless, definately not digital cordless, wait for dial tone then press remote. This used to work some years ago on analogue phones, haven't tried it for some years, don't know if it works on digital phones.

I have been looking into getting one of these http://www.mytoolsforyou.com/automotive-tools/BSL-500010.html it is an IR and RF tester. This is the best deal that I can find it for, and it comes with 30 batteries. Sell the batteries=FREE tool.