hid headlights drl problem

Hi, I am looking for a way to stop 9 volts but allow 12 volts in the same L33 circuit wire? I have a Jeep Patriot 2011, the 9 volts comes from a circuit board and goes straight to the high beam, which is a reduced dimmed light for the DRLs (Daytime Running Lights), when the high beam is activated it puts 12 volts in the same L33 circuit shown in the diagram; the low beam is activated by a separate circuit board. The HID harness is plugged into the connector going to the headlights and has a solenoid in the HID projector that operates the high beam with the reduced 9 volts; when the car is put in drive the high beams (DRLs) come on, which even during the daytime are blinding for other drivers. What I am looking for is some way to restrict the 9 volts going directly to the high beam wire (L33 WHITE/ pink, which operates the HID harness solenoid turning on the high beams) and effectively turn off the DRLs, but allow 12 volts if I need to use high beams. If I could stop the 9 volts and allow 12 volts I would then add a relay using the 9 volts and turn on my fogs, which would replace the DRLs. Thanks. Have a great day.

Paul

Use a comparator, eg LM339.

This is because the HIGH BEAM filament/bulb is used at lower power for DRLs, so yes, it would pull the bulb down for high beams. There should be a KIT that lets it operate correctly with your Vehicle, -vs- buying a universal HID kit. If you remove the wire, which you can do but risk an indicator, then you won't have high-beams when you actually need them. You can tap into the 9V wire to trigger a relay, for 12V in and out of the relay to make your FOGS the DRLS. Then, after the splice, you need to input a circuit to reduce the voltage to a point where the controller doesn't trigger the solenoid to the HID bulb, but WILL when you put the high beams on, thus 12V is now on the line, and it won't effect the relay to the fogs. Test voltages to the solenoid wire harness, see which will and will not trigger the solenoid. So, if 9V does, try 7V. IF 7V does not, then you need the circuit to reduce to 7V after your splice to the relay, thus that 12V takes you back up to 9V, enough to trigger the solenoid for the HID high-beam. An LM339 Comparator will be able to handle the current load needed for this application by itself. The power supply voltage ranges are +2 voltage to +36 volts, but the supply current is 0.8 mA; and in turn the output current (positive supply to output) is 16mA typical (6mA minimum). You can use the comparator with a relay though. The circuit would require you adjust resistance: http://www.eleccircuit.com/low-voltage-battery-monitor-by-lm339/ See the first circuit diagram, but replace the speaker with a RELAY, that triggers at the right voltage. You don't need the LED either... So, basically, the circuit will interface into the wire AFTER your splice to the FOG lamps. The PROBE inputs will be the L33 wire after the splice, and then ground. If this is all too complicated, you will have to call the company that made the HID to see what you can do about it.

Hi,    Thanks for the help. Attached is the circuit I will be using: What will the comparator circuit look like? I am trying to disable the DRLS, but have the headlight low beams come on instead, while still maintaining the use of high beams when needed. Is there another way to achieve what I am trying to do? I am not that familiar with electronics, do I just buy the comparator parts, fit them on a circuit board and wire the input and output wires to it?Have a great day.

Paul

Not sure if you can see the drawing well enough? Have a great day.

Paul

paulmackie wrote: What will the comparator circuit look like?

I'm talking DIY stuff like ermicro.com's Working with the Comparator Circuit, electroschematics.com's 12V Battery Level Indicator Circuit, LM339 Solar Tracker PCB. There may be commercial circuits but probably expensive, and there are alternate solutions - eg PICAXE 08M2 etc.

That is great info,and will have to study it, I understand the drawings electrically, but have no. experience with electronics. Can someone put together a parts list and draw me a circuit that involves adding a relay to bring on the low beam headlights instead of the DRLs, and a comparator to stop 9 volts, but allow 12 volts to the high beam headlights. I am using a 12v relay to switch the low beams on, can that be added to the circuit board and have everything in one unit? Would the attached drawing be what I need or will there be changes? Where would my high beam wiring connect to in the comparator circuit? It looks like the +, with - from a ground, and headlight Vout? Thanks for all your help. PaulHave a great day.

Paul

From what I understand, the high beam headlight circuit wire comes off a circuit board and goes to the high beam headlight. Two voltages run down the same wire, 9v for the DRLs and then 12v for the high beams, I was using regular headlamp bulbs, so the DRLs came on dimmed and the high beam bright. I have since fitted HIDs with a single bulb and the high beam is a solenoid that drops a metal plate exposing more of the bulbs light for high beam. So, I need the Comparator to restrict the 9v (which is operating the high beam solenoid as soon as I put the car in drive), but allow the 12v to operate the high beam solenoid. The relay shown in sketch will bring on my low beam headlights, which will act as my DRLs. Hope this makes sense to everyone. I am currently resolving this problem by turning on my low beam headlights after I start the car and before I put the car in drive; but if I forget to do that, then the high beams come on as DRLs and are so bright they blind people during the day. The company I got my HID parts from said they will configure the harness to solve the problem, but up to now I am still waiting. Really appreciate any help with this. Great forum by the way. PaulHave a great day.

Paul

You are not 'stopping' 9V etc - you are merely sensing what voltage is on that line and switching lamps (relays) accordingly. The circuit & componentry etc is the DIY part. IMO the similar resistor based door triggers should help.

I saw this on another forum: There may be a problem with the 9v DRL feed not being a DC voltage, but a 75% duty cycle PWM of the 12 Volt car power supply. You may need an RC integrator on the 9/12 volt line. Not sure how this affects the circuit? but read that a comparator would not work. Has anybody any ideas of what the circuit shoud be? Thanks guys. Paul       Have a great day.

Paul