These early Fords Fiestas escorts ect often developed indicator faults due dust poor connection in the hazard switch unit, which often was eleviated by rapid pressing of the hazard button on and off, you could also try using a switch contact cleaner such as servisol. also check indicator relay if all fails replace hazard/indicator switch normaly same unit.
L.J.B Autos Wolverhampton.
October 2012
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