R/S Relay voltage issue

I psted this in VIDB, but thought this may be a better place.

Installed the R/S and everything is fine, except I did not hook up domelight, door locks etc, because I planned on tapping inot the horn relay so when the vehicle is locked/locked it starts (My wife wanted the original key fob).

Issue:

Chyrsler seems to use a lower (-) for the horn ouput when you lock the vehicle, so the (-) activation of the unit will not respond, I tried a relay and still no luck. If I place to battery ground w/ and w/ out the relay it works. Any help appreaciated, I do not wish to rip apart the vehicle and hook up the rest of the features. I got about (-)386Mv on the meter form he relay using the key fob. I need to figure out how to beef up the (-) output.

I have the relay wired as such:

87 - Ground

If I take 86 and touch to chassis ground it does start the R/S, it seems that the (-) output from the horn relay will not power it. If I honk the horn twice it works, but the key fob lock/lock won't.  Looks like I need to come up with another plan...