Daytime running lights tied to switch

[55BigBlock]

I have an auxiliary battery for my lights and accessories on my 2010 Precedent. I want to wire the daytime running lights so they come on with the switch is turned on and off when the switch is off. I'm sure I'll have to use a relay somehow. Anyone have any ideas?

[BTMF]

Originally Posted by 55BigBlock

I have an auxiliary battery for my lights and accessories on my 2010 Precedent. I want to wire the daytime running lights so they come on with the switch is turned on and off when the switch is off. I'm sure I'll have to use a relay somehow. Anyone have any ideas?

What kind of light kit do you have?
because I have daytime running lights on mine with the alpha body. and it comes on with the headlights automatically unless you unplug the little pigtail by the harness to turn them off.

[55BigBlock]

My lights are an older kit. I'm adding some DRLs I found online.

[BTMF]

Originally Posted by 55BigBlock

My lights are an older kit. I'm adding some DRLs I found online.

Oh ok.


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[yawood]

Originally Posted by 55BigBlock

I have an auxiliary battery for my lights and accessories on my 2010 Precedent. I want to wire the daytime running lights so they come on with the switch is turned on and off when the switch is off. I'm sure I'll have to use a relay somehow. Anyone have any ideas?

Yes you could use a relay. You will need the T9AP1D52-48 general purpose 48V relay (Mouser Electronics or elsewhere) because the key switch is 48V.

The main terminals will control the +12V from the battery to the running lights. If you run a new wire for the running lights the key will operate the running lights separately and leave the other lights and accessories as they are. The negative from the running lights goes back to the 12V battery (or joins the other negatives that are going back there).

[55BigBlock]

Originally Posted by yawood

Yes you could use a relay. You will need the T9AP1D52-48 general purpose 48V relay (Mouser Electronics or elsewhere) because the key switch is 48V.

The main terminals will control the +12V from the battery to the running lights. If you run a new wire for the running lights the key will operate the running lights separately and leave the other lights and accessories as they are. The negative from the running lights goes back to the 12V battery (or joins the other negatives that are going back there).

Thank you for your reply. I'm thinking about using a Double Pole key switch. That would solve 2 problems one, the lights, and the other is the common key problem. It would keep someone with a CC common key from driving off while my back is turned.

[WalterM6]

I see one issue with yawood's post but you may want it that way. The way it is shown the running lights would be on all the time. If you activate the relay with the light switch instead of the key sw you can wire it so that the running light turn off when the headlights are turned on. I believe the light sw is 12v so you would need a 12v relay instead of a 48v.
My 2¢

[yawood]

Originally Posted by 55BigBlock

Thank you for your reply. I'm thinking about using a Double Pole key switch. That would solve 2 problems one, the lights, and the other is the common key problem. It would keep someone with a CC common key from driving off while my back is turned.

That would not work because the key switch is 48V but the lights are 12V (which comes from your 12V auxiliary battery). The only way you can switch 12V with the 48V key is with a relay. By all means change the key switch to an uncommon one but then hook it to the relay as I have shown.

WalterM6; I thought that the idea of running lights was that they were on all the time whenever the key was on. It doesn't really matter if they're on when the lights are on but it is possible to hook it up so that the running lights go off if the lights are switched on.

In that case you use a double pole, double throw switch for the lights. The 12V line then goes through one throw of the switch as well as going through the relay. The lights go through the other throw of the switch. The switch then either activates the lights and deactivates the running lights or vice versa. The relay still only allows the running lights to activate when the key switch is on.

55BigBlock; if you want me to put that in a diagram, just say so.

Cheers.

[55BigBlock]

Yawood, I appreciate your interest in my question. I need a little help understanding why a Double Pole key switch would not handle both functions. One side of the DP switch handles the SPST function for the 48 volt cart, the other side handles the 12 volt + for the DRL. The DRLs are stand alone lights, independent of the headlights. They're LED and draw less than 3 amps. The switch is rated at 5 amps. Thanks again for your help.

[yawood]

Originally Posted by 55BigBlock

Yawood, I appreciate your interest in my question. I need a little help understanding why a Double Pole key switch would not handle both functions. One side of the DP switch handles the SPST function for the 48 volt cart, the other side handles the 12 volt + for the DRL. The DRLs are stand alone lights, independent of the headlights. They're LED and draw less than 3 amps. The switch is rated at 5 amps. Thanks again for your help.

You know what Dennis - you are right. Sorry for not seeing that straight away. If you keep the two circuits separated then you could do what you are proposing. The key operates the 48V system as normal and the 12V system just uses the other poles to switch those lights on and off.

I'll go back into my box now. Mind you, my solution would work too.