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As I drive around in 15 to 25+ year old vehicles, I find myself looking at new cars with their LED daytime running lights with some envy -- especially on dim days and early evenings, when it's not quite time for the headlights but something to make a dark truck stand out would be nice.

 

Mounting an inexpensive set of LED lights of some kind wouldn't be difficult, but the question is how to wire them up. I don't want them on all the time, but I also don't want to have to remember to flip a switch to activate them or turn them off. At the moment, I'm mostly driving my late wife's XJ, and that got me thinking about running the LEDs off a normally closed relay, and using the neutral safety switch to remove power from the light relay when the shifter is in neutral or park.

 

Is this possible?

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Don, that's a great solution if you have conversion headlights, but I still use sealed beams. And your description calls for the city lights to be activated by the headlight switch. I'm looking for a way to have some LED lights come on automatically,  but NOT be on when the vehicle isn't in gear. Like the way Generous Motors does their daytime running lights.

 

But -- our transmissions and shifters don't have a switch that turns on in the Drive position, so the best I can think of is to have the lights default to ON when the ignition is on, and use the neutral safety switch to control OFF.

 

DC -- the late wife's XJ that I'm driving these days (until I get my '88 running again) is a 2000. The '88 is a 5-speed -- that's an entirely more complicated problem to accomplish the same goal.

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Canadian Jeeps are fitted with a daytime running light mod from the factory. You can Google them.

 

For example my son's 96 XJ (5 speed) light go on auto after about 1 meter of movement...the off auto with the key.

 

Maybe you can use a similar control for just your LED's

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Interesting. In my experience the DRL's just turn on the low beams when the engine's running. But then they only worked on one of the three XJ/mj's I've owned. I believe DRL's were an option in the US of A, and that you should be able to get them working just by plugging in the module to the existing connector.

If I had another working module I'd offer to send it down but I gave that one away already to someone who actually cared about DRL's... In my mind the low beams by themselves aren't adequate for poor-weather visibility because they don't turn on the tail lights.

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Yes, the factory daytime running lights just use the low beams (I think perhaps at reduced voltage, but I've never had them so I'm not sure about that). That's NOT what I want. I'm looking for a way to add LED running lights, without having to use a switch to turn them on and off.

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This DRL "switch" is pretty cool, stand alone, and simple to install. It must work by sensing the increased battery charging voltage when the engine is started and keeps the DRL's on until you shut the engine off and the battery settles down to it's lower normal "at rest" voltage state.

 

I can see this might be problematic though if your charging system isn't working as it should and/or if the your battery is dying.

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This DRL "switch" is pretty cool, stand alone, and simple to install. It must work by sensing the increased battery charging voltage when the engine is started and keeps the DRL's on until you shut the engine off and the battery settles down to it's lower normal "at rest" voltage state.

 

I can see this might be problematic though if your charging system isn't working as it should and/or if the your battery is dying.

 

 

It might work on seeing the ripple output from the alternator.

 

Kinda like the Soundracer.

 

 

:rotf:

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I have to get one of those for my 2.5.....

 

But back to the LED question ...I think I was misunderstood.... Do not wire the drl mod to the low beams...use the output to trigger your led relay...

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Affordable, and looks easy to install. But the wiring diagram doesn't make any sense -- from the diagram, the lights would be on all the time.

 

 

It's either as Hornbrod said, and it senses alternator charge due to increased voltage (turns on at 13V or so), or it is as I suggested and senses ripple current and turns on.  Both methods do have certain risks, IE a system like GM's intelligent charge controlling might not trigger at all times if it is voltage sensing, or it may not trigger with certain 'smoothed' or low RF alternators if it is sensing ripple output.

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Instead of using the grounding of the NSS (P/N) to control the coil side of the relay, which would cause the LED's to flicker when the gear selector is moved from Park to Drive or Reverse to Drive and visa versa, control the coil side of the relay using the (D)rive circuit (TCM) on the NSS and just ground the coil side of relay. I believe the connector is at the rear of the rocker cover. Supply the relay with a RUN circuit to the LED's. Should only come on in Drive.  Down fall is when the key is ON and the engine is OFF, placing the gear selector in Drive will activate the LED's, also no manual override. Applies to AUTO's only.

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