I've bought these LED car door lights for use in a prop device, but I'm having trouble with what I assume is a reed switch.

They are designed to turn on automatically when a car door opens, so in their package they have a small metal magnet stuck behind the battery, removing it turns on the light.

The problem is this connection seems a little inconsistent, and I want my prop to have magnets on it too, as it stands they interfere with the light.

Can anyone tell from this picture of the circuit if it is indeed a reed switch, and which part I could remove and bypass? I already tried with the tiny black box off to the side numbered 6207 assuming it was that, disconnecting it has given me weird results where now tapping one of those contacts turns on the LED, even though I only tap one contact and not the other two.

I'm ok with simple LED circuits, but I've rarely worked with circuit boards and don't have a clue what I'm doing, just want to eliminate the magnet switch so I can wire in my own switch!

Thanks in advance,

Manny

 

If there is a reed switch it is not in that board. It should be near where the magnet is.

Is the battery in the other side? How about a pic?

 

The HM6207 is a micropower, ultra sensitive hall effect switch. It is mainly designed for battery-powered, hand held equipment. HM6207 includes hall sensor, a small-signal amplifier, dynamic offset cancellation and CMOS output.

Datasheet here.

 

If there is a reed switch it is not in that board. It should be near where the magnet is.

Is the battery in the other side? How about a pic?

Battery case on the other side, in the second phot I snipped off one to solder on my own holder for easier access.

 

So it is the hall effect sensor that detects the magnet. If you don't want to use it, just keep it away from magnets and it will be always on.

 

The HM6207 is a micropower, ultra sensitive hall effect switch. It is mainly designed for battery-powered, hand held equipment. HM6207 includes hall sensor, a small-signal amplifier, dynamic offset cancellation and CMOS output.

Datasheet here.

OK, so I really need this to work with magnets not interrupting. I've gone back to the one I disconnected the HM6207 from, and I still can't understand how the circuit works without it. It's definitely no longer magnet triggered, and it works when I just tap the ground pin with my finger. How can I now wire it to just be permanently on? I'm assuming there is somewhere I can solder to give this a continuous circuit.

Here is pictures of it off and triggered with a scrap piece of metal.

 

How can I now wire it to just be permanently on? I'm assuming there is somewhere I can solder to give this a continuous circuit.

Try a jumper between the two pads marked with the red line, obviously with the sensor removed.

 

Try a jumper between the two pads marked with the red line, obviously with the sensor removed.
View attachment 289499

That did it! Thanks a lot everyone

 

Indeed! the black rectangle with 8 legs is an IC.
To reverse the logic you can have a second magnet to cancel the field of the provided magnet. That will take a bit of experimenting but it can work.