Voltage Fluctuation

[alexanderfoti]

Hi all

On my diesel bike, I have a 12v fuel pump (piston type). As its a piston type pump, it causes voltage fluctuations.

I also have LED brake lights, and it causes big problems with the brake lights flickering. It failed its last MOT on this. I disconnected the fuel pump, it passed, then I re-connected it again.

This is what it looks like:

I'm trying to fix it now, and I'm thinking, I can use a constant current driver to sort it out, like this:

http://www.ebay.co.uk/itm/5A-Constan...item2ed0148934

Any ideas on what I can use otherwise, something nice and easy like a massive capacitor

 

[duke37]

You probably have a massive capacitor, called a battery. The problem could be voltage drop along the cables. Try connecting the pump directly to the battery.

 

[alexanderfoti]

Bingo, hole in one.

Relay on its way to connect pump directly to the battery. Thanks!