[jax32]

I'm upgrading my tail lights and turn signals to LEDs (I have a 32 roadster with a 350 Chevy). The electronic flasher that I bought must be grounded (no problem there) and the instructions say the power lead must be fused. But there is no indication what type of fuse I should use, meaning amps and slo blo or fast blo. Anyone have an idea?

[66GMC]

The flasher manufacturer just want you to provide fuse protection for your flasher in the case that a wire gets grounded out or the load is higher than the flasher is rated for.


Grote 44890

Grote states a min of 1 Amp fuse, a max of 20 Amp ... as stated on the flasher.

Passenger Cars/Light Trucks LED Compatible EL12, 20mA~25A; Electro-Mechanical Flasher; 1 to 12 Lamps; 400 Hours; 12 Volts, 300 Watt

This flasher is rated for 300 Watts.

Using the formula:
Amps = Watts/Volts
Amps = 300/12
Amps = 25

So, if this flasher is capable of flashing 12 bulbs, (25/12) the 2 amps per incandesant bulb makes sense.

LED's will draw significantly less, so IMO I'd start with a 5A fuse and go up from there if it blows.

[jax32]

Thanks 66GMC. I think I'll try your idea of starting with a 5 amp fuse.

[jax32]

66GMC, There already was a fuse for the turn signals but I went ahead and put a fuse on the hot side of the flasher (it's a two-pronged unit, excluding the ground). I did that on the assumption that the flasher needed a fuse independent of the turn signals. Was I wrong>

[66GMC]

Originally Posted by jax32

66GMC, There already was a fuse for the turn signals but I went ahead and put a fuse on the hot side of the flasher (it's a two-pronged unit, excluding the ground). I did that on the assumption that the flasher needed a fuse independent of the turn signals. Was I wrong>

You could have probably just stuck a 5 amp fuse in the original location.
The way to tell for sure is to test the flasher with both fuses installed.

If it works, remove the one in the original location and see if it still works.