Wiring help needed

[JCasper]

So after reading the article in the TDR and seeing the thread recently here I decided to add two auxilary fuse blocks, just like in the TDR article.



One I powered directly from the battery with an inline fuse. The other I powered from the battery through a relay using the cigarette lighter to trip the relay. That way that block only has power with ignition on.



I have some auxilary lights on the back of my truck that I powered off of the ignition on block through a relay. The power for those comes from the fuse block through the relay and to the lights. That relay is then tripped by a switch that is also getting power from the same fuse block.



From that block I am also powering my Westach gauge. When I turn on my auxilary lights it makes my boost gauge wig out. It will go up to like 20 and stay there until I turn my truck off.



For now I moved the power source for my auxilary lights and the switch to the always on block and it seems to be fine.



Any ideas on what could be causing my problem would be appreciated.



Everything worked fine before I added these fuse blocks. Before the lights got power directly from the battery and the gauge got its power from the cig lighter. I just like the idea of adding the fuse block to clean things up a little.

 

[rbattelle]

What you did sounds right from an electrical point of view. The crazy behavior of your gauge sounds to me like you inadvertently wired the gauge and the auxiliary lights in series instead of in parallel. This would cause the current in the auxiliary lights and the gauge to be equal, which is bad.



To make parallel circuits, each component should have it's own independent connection to the (-) and (+) sides of the circuit. In this diagram, all the ammeters ("A") are connected in series while the voltmeters ("V") are connected in parallel.



If you can verify that the circuits are indeed parallel, then there must be some interference occurring between the lighting circuit and the gauge circuit, possible via the ground. Do they use a common ground? If so, consider separating them, and running the gauge ground directly to the battery negative terminal.



Ryan

 

[Bob V]

Might check the ground for the relay and the gauge

 

[JCasper]

Might check the ground for the relay and the gauge

Thanks Bob, I was going to do that tonight but I am beat. My wife and I joined the gym and we had a meeting with a trainer tonight. I can barely move now. I will check it tomorrow.