viper 5904 will not start by key

Viper will not honor a warranty on a DIY install.  Even if the internal Starter Relay is not returning to the N.C. position for Pin 30 to 87a, you might still make the Viper remote start work . 

There are a few things you can try.  First, reconnect the Civics cut starter wire and make sure everything works normally.  Then connect the Vipers' Violet Starter Output wire and see if you can get the remote start to function ( as suggested by Jim Hunter ).  If this works, the only thing you lost was the StarterKill / Anti-Grind feature.  These can added later using an external relay and other Viper outputs. 

If the remote start function still doesn't work (because of no output on the Violet wire), you can check to see if the Viper's (-) 200mA Starter Output is still working properly.  If it is, you can wire up an external Starter Relay to connect to the Civics Starter wire.