Turn Signals, Working only when the headlights are off Options

[Rob-O 1167]

Like the topic title says, the turn signals light up and 'blink' when the headlights are off, perfectly normal operation. But once the headlights are on, I can hear clicking in the dash but the turn signals do not 'blink'. I also noticed that the light in the tach never flashes and seem to remember that there was a thread about the circuit running through that lamp. Anybody have any ideas? I'm just trying to tie up some loose electrical gremlins..

[Mike Bellis]

The other possibility is a bad ground at the relay or switch. The signals may be pulling a "ground" through the turned off headlights. This is exactly how the fog light switch works. The fog light switch gets its power from the low beam and its ground through the high beam turned off. When the high beam turns on, the "ground" to the fog light switch becoms positive and shuts off the fog lights. It's not really a "ground", it's just MORE negative than the power lead and that will allow current to flow over it.