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Relay for Headlight Signalling 120-130

Ok Here's one for you Antique electrical geniuses .... there are three connections to the Headlight Signaling Relay ... a grey, a double red and a black. There are absolutely no markings on the relay .... how the heck do you hook this up? The old relay was removed and an aftermarket one of too light current rating was installed and gave up the ghost .. so I don't have the original one to go off any help would be greatly appreciated ....

According to HAYNES .. the BLACK goes to the headlights,the GREY goes to the switch on the signal light stalk .. however, HAYNES says that the one going to the fuse block should be BLACK... and I have a DOUBLE RED wassup wid dat ??? The BLACK line appears to be hot .... so is probably from the fuse box .... Sooo maybe the double RED is the one that should go to the headlights ...... OK so which connections on the relay do they attach to ???????
--
Brett Sutherland & the 1.5 million mile 122 Canadian








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    Relay for Headlight Signalling 120-130

    Here's the general concept with a relay:

    You've basically got four connections, and they've got all sorts of names. I'm using the ones I think are most descriptive for your purposes.

    You've got a supply, an output, a trigger, and trigger ground.

    The relay is a switch, just like a light switch, but instead of using your finger it uses 12 volts DC to flip the switch.

    When 12 volts is present, the switch is on- no 12 volts, switch is off.

    The supply and output are the two "switch" connections. When 12 volts is present at the "trigger" connection (the electrical "finger") the switch is on. It really doesn't matter what the "supply" and "output" are connected to: you can hook up the fusebox headlight power supply on one and the headlights on the other and as long as you've got the trigger set up right the headlights will come on.

    The trigger is the wire from the signal stalk. This provides 12 volts DC when you pull the stalk. The trigger ground is provided by screwing the relay tightly to the steel of the car.

    So- how to test?

    Attach the relay tightly to the body of the car in such a way that you can connect wires and a tester as needed. Have a continuity tester handy. Connect the "trigger" wire (from stalk) to the appropriate connector on the relay (grey). Check for continuity across the two other connections- "supply" and "output". They should read "open" or "zero" on the tester (or no beep if the tester beeps).

    Now turn on the ignition, turn on the headlights, and pull the stalk for high beams. Check continuity across "supply" and "output". It should now be "closed" or "1.0" (or now you'll get a beep). This means the trigger has made the "finger" flip the "switch".

    If you are feeling daring you can just hook the relay up as follows-

    Grey- stalk wire
    Black- fusebox supply voltage
    Double Red- headlights

    Bear in mind it's your choice to bet I'm right without testing it first....

    -Dylan








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      Relay for Headlight Signalling 120-130

      Hi Dylan ..... Just went out and tried the relay with the BLACK in the center position and looking at the bottom of the relay with it bolted in place ... tried first with the GREY on the left and the double RED on the right ... NADA so I switched the two outside lines ... still NADA the only reaction I get is if the supply(BLACK) is connected to the right terminal then I hear the relay click ... BTW I hold a Canadian ADVANCED HAM Radio ticket and DO know my way around an electrical circuit .... the BIG problem here is that the terminals on the relay are not marked ... the OTHER problem might be that I was given a faulty relay ... but seeing as I am getting a click when the hot wire is connected to the right hand terminal I am hoping that it is OK ....can't lay my hands on my continuity checker at this moment.....
      --
      Brett Sutherland & the 1.5 million mile 122 Canadian








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        Relay for Headlight Signalling 120-130

        Gotcha. Good to hear you know your way around electronics. You never know what sort of person you'll run into around here.

        I'd wait 'till you got a 'meter of some kind, or crack the case and look inside.

        Okay wait if the black wire (12v supply) on the "right" terminal makes the relay click, you've found the "trigger" I was talking about earlier.

        I guess if I had no meter I'd hook the supply DC up to mystery term #1, headlights to mystery term #2, and run a jumper from #1 to the "trigger" term that makes the relay click. If your headlights turn on now, you know the relay is good, yes?

        Hope this helps-

        -Dylan








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          Relay for Headlight Signalling 120-130

          OK Dylan .... thinking out loud here ... the Right contact is the trigger .... so shouldn't the GREY line that goes to the switch be connected there? Then seeing as I have had no luck with the hot lead on the center ... move that to the left and the double RED to the center ..... OK going out to try that ....

          Back and still no joy .... I had blown the bottom red fuse on the fuse block but from what I could could tell the only circuit I found out was the dome light ... EVERYTHING else worked .... hard to check the brake lights though ... replaced the fuse and still NADA ... beginning to think this is a BUM relay .....
          --
          Brett Sutherland & the 1.5 million mile 122 Canadian








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            Relay for Headlight Signalling 120-130

            Yep that's pretty much what I meant about "finding" the trigger- the grey lead would go there once everything's figured out.

            I guess the next step would be to confirm the black and red leads when touched together cause the high beams to illuminate. Just try touching them together and see if that works. If so, then you know you've got all the right wires, and they're all performing as we expect them to.

            The dome light circuit may also power the 12 volt trigger that is supplied by the turn signal stalk when you engage the high beam signal function.

            I would start here by hooking the grey trigger lead to the relay where we think it goes, then pull on the stalk and make sure the relay makes a click. If not, then either the relay's faulty or it's the wrong type.

            Hope that helps.
            Dylan








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    Relay for Headlight Signalling 120-130

    Brett;

    Those colors sound correct. The two Reds are the High Beam wires...one from the foot switch and one going off to the lights.



    See also: http://www.intelab.com/swem/headlight_control_upgrade.htm

    Cheers








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      Relay for Headlight Signalling 120-130

      Ron .. The URL for the first page just gives me one line of machine language .... What I really need to know is which of the three terminals on the relay to connect which line to ....

      --
      Brett Sutherland & the 1.5 million mile 122 Canadian








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        Relay for Headlight Signalling 120-130

        Brett;

        The graphic in my first post shows terminal numbers and wire colors...and works just fine on my comp....but if it doesn't work for you, just go to the article, the graphic is there too.

        http://www.intelab.com/swem/headlight_control_upgrade.htm

        Cheers







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