warning lights

[ALS4B]

having promblems hooking up warning lights for oil and alt . using LEDS, have put a fuse in line soon, as i hook up the earth side it blows the fuse . is there a way around this ? any help please.

[tweake]

need to know how you have wired them up.

[ALS4B]

a new wire from the oil sensor back to dash same with the alt as well

[Mattman]

What spec are the leds? They don't usually like 12v.

Perhaps a diode to prevent current draw through the LED.

Matt.

[toominator]

An led is a diode so adding another one won't do anything. Probably needs a resistor to bring the voltge down, but not sure why the fuse would blow instead of the led burning out

[tallsam66]

You need a resistor to lower the voltage.id expect the led to blow not the fuse ..something else is wired wrong.

Have a read of this ...will point you in the right direction.

http://white-leds.co.uk/led-wiring-guide.htm

[tweake]

what led's ?

some led bulbs come fitted with the required resistor etc. but a straight led will draw high current and cook itself if it doesn't have a resistor or some form of current regulating.

leds typically fail closed circuit (ie opposite to light bulbs) so will act as a short and blow a fuse (assuming no current regulation or resistor).

[sibainmud]

what led's ?

some led bulbs come fitted with the required resistor etc. but a straight led will draw high current and cook itself if it doesn't have a resistor or some form of current regulating.

leds typically fail closed circuit (ie opposite to light bulbs) so will act as a short and blow a fuse (assuming no current regulation or resistor).

Best answer so far
The clue is in the name....L light E emitting D diode... DIODE.
Power passes one way but not the other. While using a led for oil light is ok and straight forward, using one for an alt light is very difficult. Alts use an incandescent bulb for a reason. When the key is on but not running positive is supplied to one side of bulb and the negative is supplied through the regulator, giving the excitation for the alt to work. When the engine starts and the alt starts working, the reg puts out positive causing the light to go out. Manufacturers use this to power all sorts of warnings too, so it becomes quite complex

Hope this helps.

[ALS4B]

all sorted know ,all i had to do was hook the earth side to the oil sensor and the positive wire to the acc wire works just fine ,soon as it starts the LEDS go out simple as know