Car Headlight Alarm

[will.i.am1]

I tried to make the circuit with a diode to stop the current go backward. And this is what I come up with(Please refer to attached circuit).

There are two things wrong with the circuit;
1. The current is not going into the buzzer only the voltage does.
2. The current (12Amps) is flowing to the ground which it shouldn’t do.

I need your help guyz as I might have put a wrong connection somewhere which is causing the circuit to flow the current to the ground.

 

[Ramussons]

What did you want to do in the first place?

In the present circuit,
JI lights up X1 and sounds buzzer,
J2 lights both X1 and X2 and soundsw buzzer.

Ramesh

 

[will.i.am1]

I want buzzer to sound when the headlights (x1) are on and engine(j2) is off. And when the engine and headlights both are on; nothing should happen.

 

[ericgibbs]

hi will,

As Ramesh says it should work.

I suspect that the buzzer resistance is set to zero ohms.

Eric

 

[will.i.am1]

& when both (j1) and (j2) switches are on buzzer should not sound. btw Ji is for headlights and the j2 switch is accessory line /engine.

 

[ericgibbs]

& when both (j1) and (j2) switches are on buzzer should not sound. btw Ji is for headlights and the j2 switch is accessory line /engine.

hi will,
I follow what you are asking.

But you cannot do it using just diodes.

E.
OT: I'm a exRotherham lad.

 

[audioguru]

Modern cars automatically turn the lights on when it is becoming dark outside and turns them off when it is becoming light.

When the car is turned on then the lights automatically turn on for dimmed daytime running lights or for full low beams at night.
When the ignition is turned off then the lights also automatically turn off.

 

[Ramussons]

If the buzzer is piezoelectric, then the current drawn is only 1 or 2 mA. The circuit in the thumbnail should serve your purpose.

Ramesh

 

[Bob Scott]

Way back 40 years ago, I used a "Sonalert" electronic chime for a "headlights on" alarm. I connected the + terminal of the Sonalert to the headlight + wire from the headlight switch. I connected the - teminal of the Sonalert to the wire supplying the heater fan, which is somewhat ON at all times that the ignition is on. ( I think that an "ignition" or "accessory" terminal of the fuse box whould work also.) The normal resistance of any ignition or power accessory or fan load is enough to sink all of the current that the sonalert - teminal needs to ground.

The Sonalert chimes only when the headlights are on and the ignition key is off. So simple, no diodes or other parts required.

 

[KeepItSimpleStupid]

I did my headlight on alarm in the early 80's this way:

It works like this: If the driver's door is open and the headlights are on, BEEP!
SO, it won't buzz when letting out a passenger.
It might not work, if you have your lights on and happen to stay inside the car for hours after going to a park.

I put a buzzer in series with a diode.

The driver's door already had a diode to the dome lamp and it turned on the dome with a switch to ground,. My diode just 'OR' ed the buzzer to this switch.

the + end of the buzzer went to the headlight +12.

So, lights on, driver's door open - Buzz.

My car now, when you open the door with the lights on, they go off. I have to remember to do that if I stop for a long time. Also DRL's and lights are influenced by the parking brake.

My mom's car you can program it to do things, like turn off the lights after a certain interval. It shuts off the accessory connection to the ignition when you open the door. i.e. Turn off car, radio plays until door opened.
It's also smart and will not let your dome light run down the battery.

Both are a pain when you want to turn off your lights, so the deer will leave that's stooped in front of you. My car less so. I can turn off the engine and open the door and re-start.

Mom's car - Not sure what sequence would work.