$5.00 daytime running lights

[RF_Burns]

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.
Hubler 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

 

[Matt Colie]

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 - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit

 

[RF_Burns]

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.
Hubler 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

 

[j artz]

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

 

[JHeslinga]

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

 

[JHeslinga]

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

 

[JHeslinga]

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