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Well put this in my really bad week file too. I've got the Hella driving lights all mounted and wired up. I wanted to do a slick install and use the on with high beams feature as diagramed in the lights instruction sheet. Well I wired the on feed to the lights relay by tapping into the high beam power feed on the passenger side head lamp. Now I'm not taking power there, just getting an 'on' signal.

So I tried them out after completing the wiring etc. Turned on the headlights and things were fine (Hellas off). Then clicked the high beams on, still good (Hellas came on). Then turned the high beams off and oh no, the Hellas stayed on. Then turned the headlights off and the Hellas were still on! Now either I have chose a bad feed to turn these on (the center wire on the headlight plug) or the Hella relay is bad...

So Midlife?

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1967 351W Convertible
2000 Mustang GT
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By your description, I'd tend to think the relay is at fault. Try testing the lead you used as an "on" signal for the relay with a multimeter, once you've got the high beams off. If there is no power there, but the Hellas remain on, then your relay must be bad. If there is power there still, you'll have to do some wiring modifications.

-Brian
 
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Sounds like you wired the relay to "latch".
If you're using a Bosch relay;
Terminal 86 should be ground, 85should be +12v from the high beams, or visa versa, only matters if there's a diode in it.
Terminal 87 to Hellas, 30 to +12v, nothing on 87a.


67 coupe 289 auto
 

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Discussion Starter #4
It's the relay that came with the lights. I don't have an 87a plug though. But the others sound right. I will have to look at it tomorrow. Thanks... maybe I should just pickup a Bosch relay and use that instead?

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2000 Mustang GT
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Depends on the type of relay. A standard relay stays ON as long as there is a current through the coil of the relay. There are also types that only need a pulse to switch them ON, from then on they stay ON with or without current through the coil. If that type of relay needs to be switched OFF, another pulse - with reversed polarity - will do just that.

My advice: check the type of relay that you have. If it's a normal relay, then it's defective, or the wiring is wrong. Replace with normal type and your problems should end.
 
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