Viper 4204 Responder Error, 2001 Mercury Grand Marquis

2001 Mercury Grand Marquis. Refurbished Viper 4204. Programmed with Bitwriter. Everything works, but I keep getting a single horn honk and a two pulse error that repeats a few times on the responder remote with any function. Horn honk only occurs after unlock. All other functions get the error message on the remote (beep, beep, pause, beep, beep with red light by Func). I’ve installed a ton of DEI products, but this one has me scratching my head. The responder gets confirmation chirps, but always errors right after, even though the system works as it should. Door triggers are not connected. Tried grounding negative door trigger to see if it changed, but no change. Any ideas? The only conclusion I can draw is the refurbished unit wasn’t properly repaired. I’ve not seen a responder act this way. The 1 way remote does not get the horn hook after any function.