diode, door triggers, 02 jeep tj, 5701

Im installing a viper 5701 in an 02 jeep tj. everything is hooked up and works great except the door triggers. they are - trigger and diode isolated. The striped side (cathode?) is facing the vehicle wiring for both triggers. But the alarm always shows a door open, i tested both diodes and the drivers side tested good but the passenger one was open (no current) in both directions. i cut out the offending diode and installed a new one, same thing open both ways, i unsolder this new diode and tested it works fine! i twisted yet another diode in and again open both ways but disconnect the door trigger and it works fine. Do i just need a bigger diode or what's the deal? I was under the impression once a diode goes its dead not that it would work outside the circuit. any help would be great

Should look like that.

ya its all hooked up right. diode tests good out of circuit and bad in it

Did you originally test the door trigger before the diode, I've been installing for 20 years plus, I buy approx. 200 at a time and I've NEVER had a failed diode.