1967 Austin Healey 3000. The turn signals stopped working. When i turn them on the tach drops to zero, or about 1000 RPM if the revs are high. The brake lights also seem to make the tach drop. Could it be the flasher unit?
Probably the flasher unit going bad that's interfering with the tach signal.
Check to make sure all of your grounds are good turn signals and brake lights are stealing ground signal from dash
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