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$5.00 daytime running lights [message #310289] Sun, 13 November 2016 07:31 Go to next message
RF_Burns is currently offline  RF_Burns   Canada
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
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Senior Member
Canada has had vehicle daytime running lights since 1990. Here is how a PO implemented DRL on my coach using only a cube relay and a 30amp breaker. All the wiring is done up front under the passenger side hood access for easy wiring.

-Find an area on the aluminum plate where you can mount the relay and breaker and make the follow connections with wiring long enough to mount it there.
-Connect a wire from the center terminal of the combiner to relay pin 86
-using a voltmeter or test light determine which wire is high beam and low beam on the back of the passenger side headlight
-connect a wire from relay terminal 85 to the high beam wire
-Connect a wire from relay terminal 87 to the low beam wire
-Connect a wire from relay terminal 30 through the breaker to the chassis battery terminal on the aluminum plate.
-mount the relay and breaker to the aluminum panel.

Operation is as follows:
-Starting the engine, alternator power flows to the center terminal of the combiner
-This closes relay and powers the low beam headlights only when the engine is running
-Turn headlights ON
-Low beams operate normally, but with 2 sources of power (OEM and relay)
-Turn high beams ON
-Relay opens due to the fact the relay sees 12 volts on both sides of its coil. Relay coil current was flowing to ground through hi-beam filament.
-Low beams go out and hi beams come ON through OEM wiring.

Just an easy and inexpensive way on doing it.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: $5.00 daytime running lights [message #310293 is a reply to message #310289] Sun, 13 November 2016 10:03 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Bruce,

According to the GM original proposal to the SAE safety committee (two plus decades ago), the DRL is supposed to be about one half the power of a low beam.
Well, that was the original proposal - anyway.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: $5.00 daytime running lights [message #310305 is a reply to message #310289] Sun, 13 November 2016 16:46 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
Karma: 3
Senior Member
Yes that's true but really, who is going to check it.

I think the first ones in Canada ran just the low beam. Later they set a maximum based on running the headlights in series. I think has been reduced a couple of times since then. I know that Ford used a 50% duty cycle switching circuit in the 90's that really messed up the operation of two-way radios I was installing at the time.

I thought of making a PWM circuit to reduce the brilliance, but never get to the end of the Honey-do list to start on my list.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: $5.00 daytime running lights [message #310359 is a reply to message #310305] Mon, 14 November 2016 22:10 Go to previous messageGo to next message
rootesrefuge is currently offline  rootesrefuge   United States
Messages: 39
Registered: August 2016
Location: Nebraska
Karma: 0
Member
Just put a DRL resistor in the circuit from the relay to the low beam. Lots of manufacturers used them, should be fairly easy to find in a salvage yard. Or Google "DRL resistor".

John in Omaha, Nebraska 74 26' Sequoia
Re: $5.00 daytime running lights [message #310551 is a reply to message #310289] Fri, 18 November 2016 11:07 Go to previous messageGo to next message
John Heslinga   Canada
Messages: 632
Registered: February 2011
Location: Edmonton, Alberta, Canada
Karma: 4
Senior Member
The ONLY reason the Headlight was dimmed for DRL was to increase the Bulb Lifetime. Some strategies were to run the bulbs serially through the high beam as the resistor (some GM) and others used a Pulse width modulation Module (some Ford) The DRL also is switched by the Park Brake Circuit to turn them off if the park brake is set. (Not needed when parked and service personell eliminate electrical loads)

The $5.00 solution is simple and certainly works in its simple way. No Need to make things more complex if your interested in automatic DRL. (Of course turning on the Headlight is not too hard either. But you will make a mistake one day and leave them on, even with a warning buzzer)


John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:70 LS, Red Seal Journeyman, DTE, BEd. MEd. Edmonton, Alberta
Re: $5.00 daytime running lights [message #310564 is a reply to message #310289] Fri, 18 November 2016 13:39 Go to previous messageGo to next message
John Heslinga   Canada
Messages: 632
Registered: February 2011
Location: Edmonton, Alberta, Canada
Karma: 4
Senior Member
I should have added that when the headlights are put in serial to the High beams they are wired through the opposing sides. That way if one low beam is burned out (high beams burn out less commonly) that side will still have glow from the high beam filament. If the Low Beams were serial run then if one burns out they both quit. Then of Course Chrysler came up with a weirder concoction. They lit up the front Signal light Filament and flashed it OFF for the signal light. (which melted or damaged the plastic reflector body) (they get pretty hot in bright mode)

One other thing about having regular headlights as the DRL is that they make the signal light flash become less obvious (washing out their effectivness) many vehicles now turn the Headlight type (or separate white fixture) DRL on the turning side OFF when the signal light is flashing.

If that is what would be desired, a simple delay type Relay could be used for each Headlight. A cornering light installed at this time is only one more wire😀






John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:70 LS, Red Seal Journeyman, DTE, BEd. MEd. Edmonton, Alberta
Re: $5.00 daytime running lights [message #310579 is a reply to message #310289] Fri, 18 November 2016 16:24 Go to previous message
John Heslinga   Canada
Messages: 632
Registered: February 2011
Location: Edmonton, Alberta, Canada
Karma: 4
Senior Member
Just a bit of correction to my statement of "ONLY" I didn't realize I typed in all capitals when writing it. I really ment to say the biggest reason for dimming is extended bulb life.

Transport Canada rules state that the voltage supplied to the Headlight based DRL must be between 75 and 92% of normal. (About 10.5 to 12.9 Volts given 14.2Vot operation) That does make the lights a bit dimmer but not much given that many older vehicles such as ours have that much Voltage drop at the headlights (measure yours sometime)

HOWEVER. This rule is only for OEM!! I'm not trying to undermine the original good idea.

Mr Burns idea is still a great one that you should concider!!



John and Cathie Heslinga 1974 Canyonlands 260 455, Manny tranny and 1 ton, 3:70 LS, Red Seal Journeyman, DTE, BEd. MEd. Edmonton, Alberta
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