Blowing LED in add-on switches

Rut Row

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I have a 2003 TJ to which I'm adding a winch with a 500 amp isolator relay. I have dedicated 18AWG wire running from a 800 amp (CCA) battery through a 5A fuse to the switch and then to the isolator. The switch has a single LED to show when the isolator is activated. The battery voltage at the time the lights burned out was 12.4VDC.

I have blown the light in three switches. The first two were from Gold Coast Distributing (GCD). GCD replaced the first one and when the second blew as well, I asked for a refund which they gave. The third switch was from OTR Switch Guys (I actually like that switch better). When I called them I actually got to speak to their tech guy. He is sending me a new switch with a different resistor.

In all three cases, the light comes on when the switch is activated, you can hear the relay activate then deactivate when you turn the switch off. The second time you activate the switch, the light craps out.

I took the battery back to BatteryOne and they tested it - no issues.

The wires hot wires are dedicated. The ground from the switch goes to the body. No wire is patched into another wire.

I have two Rigid 504814 D-Series Pro DOT/SAE J583 Fog Lights and they work fine. They use the OEM fog light circuit and switch.

Anyone know what is wrong?
 
So just to confirm, you're running 12v+ from a 5A fused source, through the switch, to the isolator/relay, correct?

Sounds like two possibilities: 1) the process of turning the switch "off" allows a ground fault of some sort internally that although probably isn't problematic, causes more amperage to go through the switch than the LED can handle or 2) the process of turning the switch "off" has some backflow of current through the switch itself, likely due to the collapsing of the magnetic field within the relay.

Do you know the rated wattage of the LED's inside the switches that are being used? It is possible that a larger resistor inside the switch may help curtail an influx of current during the collapsing of the magnetic field inside the relay. Additionally, a larger diode (not an LED) upstream of the switch (with enough wattage rating) would help in place of a resistor.

Out of curiosity, why are you running a remote contactor/relay setup?

PS - dog in your profile pic is cute AF!
 
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Are you sure you are wiring the switch correctly? Many have 4 terminals. Power in, switched power out, ground, and input from dash lights. Just a thought.
 
^ X2

Sounds like you're running the power to the isolator through the LED.
 
So just to confirm, you're running 12v+ from a 5A fused source, through the switch, to the isolator/relay, correct?

Sounds like two possibilities: 1) the process of turning the switch "off" allows a ground fault of some sort internally that although probably isn't problematic, causes more amperage to go through the switch than the LED can handle or 2) the process of turning the switch "off" has some backflow of current through the switch itself, likely due to the collapsing of the magnetic field within the relay.

Do you know the rated wattage of the LED's inside the switches that are being used? It is possible that a larger resistor inside the switch may help curtail an influx of current during the collapsing of the magnetic field inside the relay. Additionally, a larger diode (not an LED) upstream of the switch (with enough wattage rating) would help in place of a resistor.

Out of curiosity, why are you running a remote contactor/relay setup?

PS - dog in your profile pic is cute AF!

you are correct. I don't know the rated watts of the LED but I'll see if I can find out. I'm running a remote so that I don't have to open the hood and manually flip the isolator switch. I'm lazy.
 
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I have a 2003 TJ to which I'm adding a winch with a 500 amp isolator relay. I have dedicated 18AWG wire running from a 800 amp (CCA) battery through a 5A fuse to the switch and then to the isolator. The switch has a single LED to show when the isolator is activated. The battery voltage at the time the lights burned out was 12.4VDC.

I have blown the light in three switches. The first two were from Gold Coast Distributing (GCD). GCD replaced the first one and when the second blew as well, I asked for a refund which they gave. The third switch was from OTR Switch Guys (I actually like that switch better). When I called them I actually got to speak to their tech guy. He is sending me a new switch with a different resistor.

In all three cases, the light comes on when the switch is activated, you can hear the relay activate then deactivate when you turn the switch off. The second time you activate the switch, the light craps out.

I took the battery back to BatteryOne and they tested it - no issues.

The wires hot wires are dedicated. The ground from the switch goes to the body. No wire is patched into another wire.

I have two Rigid 504814 D-Series Pro DOT/SAE J583 Fog Lights and they work fine. They use the OEM fog light circuit and switch.

Anyone know what is wrong?

500 amp relay is big. Sounds like you are getting a voltage spike back into the switch when you turn the relay off. The led in switches are generally wires from the switched terminal to the ground wire. When you denergize the relay you are probably getting a voltage spike up back into the switch. The voltage spike will look for a ground and the led is it. You could install a clamp I’d diode in the circuit or install a relay which turns on the 500 amp relay. The diode may be tricky to source that can handle the spike. The relay would be simple to do. Use a Bosch relay 85 to switch, 86 to ground, 30 to the 500 amp relay, 87 to fused battery, and 87a to ground.

4F10D255-730F-4621-B517-86FE9A5CF8DB.jpeg
 
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500 amp relay is big. Sounds like you are getting a voltage spike back into the switch when you turn the relay off. The led in switches are generally wires from the switched terminal to the ground wire. When you denergize the relay you are probably getting a voltage spike up back into the switch. The voltage spike will look for a ground and the led is it. You could install a clamp I’d diode in the circuit or install a relay which turns on the 500 amp relay. The diode may be tricky to source that can handle the spike. The relay would be simple to do. Use a Bosch relay 85 to switch, 86 to ground, 30 to the 500 amp relay, 87 to fused battery, and 87a to ground.

View attachment 397546

Thanks - I'll try the new switch without having it connected to the isolator relay to make sure it works then I'll add a relay just to be safe and reconnect.

Sounds funny having to install a relay to run a relay! hahaha

The winch has a max draw of 480A hence the 500A relay.
 
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Thanks - I'll try the new switch without having it connected to the isolator relay to make sure it works then I'll add a relay just to be safe and reconnect.

Sounds funny having to install a relay to run a relay! hahaha

The winch has a max draw of 480A hence the 500A relay.

Just pretend it’s a BMW, they love to do that.
 
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In all three cases, the light comes on when the switch is activated, you can hear the relay activate then deactivate when you turn the switch off. The second time you activate the switch, the light craps out.

What about running a wire back to the LED from the the coil.
That way you'll know the coil is actually energized instead of just knowing the switch is on.
 
What about running a wire back to the LED from the the coil.
That way you'll know the coil is actually energized instead of just knowing the switch is on.

Most switches with led’s do not have a separate terminal for the positive side of the led it is tied into the switch output terminal. They do add a separate ground terminal which is for the led.
 
I would have put the diode on the trigger wire, but if it works, it works! Glad you got it...