Inconsistency triggering defroster/heated seats from alarm.

[Dismay]

Alarm Viper 5901, Veh 2001 Yukon.
I have the defrost and heated seat wired in at the switch/button. The defrost takes a negative pulse, and the heated seat takes a positive pulse (i've used a relay to reverse polarity)

Both work properly about 70% of the time, but some times it seems like they get double triggered, so the defrost goes on then off instantly, and the heated seat goes from on high to on low. I'm wondering if using a resistor inline would help to "smooth" out the pulse and avoid double triggers? I seem to remember a diagram with a 2k resistor wired in for the heated seats, but I can't find it now. Any ideas are appreciatied! Thanks!

 

[Eagle]

maybe a .05 uf capacitor, not a resistor?

also, you could be experiencing contact bounce, or flyback voltage... is there a diode on the relay to prevent flyback? Is it a tyco/bosche relay or some off brand?

anyway that 's my thought off the top of my head