That was the only logical answer i came too but discounted it because a/ black wire is a earth b/ you don't normally use earth feed as a switch line
Surely indicators/hazard relay are already earthed permanently ??
I know i'm being a bit thick but from diagram i cant see when alarm activated it connects to flashers
Looking at normal indicators wiring diagram you can see how indicators get their feed from hazards switch or indicator switch
If there was a fault with relay would this stop flashers working when you arm the alarm ??
or is there another relay on the alarm to activate flashers when arm/disarm ?