When left on
Flood lights on my truck blow fuse (30A)

Where would you start looking?

Lights are on rear of a garbage truck. Used when driving in reverse or while operating hydraulics in dark.

So

I guess it could be blowing fuse when PTO is engaged while lights are on?

What wattage are the lights and check the wires going to them against ground. May have a short in there some place

Yeah

Was gonna run the wires out 1st. Just wanted to pick your brain for anything else 1st. I also read somewhere that the PTO could be causing it? I'm not sure why that would be? But this truck does have a problem that runs the packer hydraulics. And the lights and PTO are almost always on at same time because they go hand in hand when operating in the early morning hours.

Also

Don't know wattage on lights. Truck is relatively new to me. There are four flood lights hooked up to same fuse. That may also run back up beeper? Beeper and lights went out at same time I think. So, maybe circuit is to small of amps for everything to be on at one time for any extended amount of time?

You can buy a 30A breaker which plugs right in to a flat fuse holder. It will reset as soon as the load is removed. I had that issue with a remote control spotlight. Spotlights pull a lot of amps, and when the button was pushed to turn the spotlight to the maximum limit, the electric motor would load up and burn the fuse. The breaker allowed me to carry on without having to get out of the truck and change the fuse.

I think I may switch to LED?

Look at your fuse. Does it look like a grenade went off. If so that usually indicates a direct short. If it doesn't then it usually indicates it's a overload on the circuit. Sounds to me you have to many lights for the size wire and fuse in that circuit.

Russ

Yeah

Grenade! Whole in line fusable link is smoked

Check the wire run. It may have chafed through in a spot and is making contact with ground. The PTO switch is just a pressure switch. Should not cause any problems like that. It either works or does'nt IE lights come on or not.

If it's easy to unplug the lights at the back of the truck, as close to the lights as you can get, then do that.
It might be an easy way for you to see if it's a short in the wire or the load is too much for the fuse.
If they have a common ground wire, then maybe unplug that. It will leave the power wire in tact and remove the load from the circuit.
Joe

Yup

I'll disconnect lights and cut fuse out so I can test for short to ground. But I'm concerned with how many lights are on that circuit such as half says above. So I'll switch to LED while I have them disconnected just to make sure.

But! What I'm reading about the hydraulic pump. Is that on these trucks it is possible to have a power to power. So basically:. You turn lights on in the morning while it is dark so that you can back down someone's half mile long drive. Pump is off (open) so it draws amps off light circuit?

I wouldn't start changing things until I found the problem. Figure out whats wrong with it instead of just throwing guesses at it.

Yup

Take all bulbs out first,that will just leave the wiring. If it still blows,a wire is chaffed. If no blow start putting light bulbs back in one at a time. If it blows then it is more than likely an overload with the backup beeper since you already tested the circuit with no load and the wiring should be OK.

Found problem!

It was a direct short to ground.

Now I have a back up beeper to contend with. The original beeper was disconnected for reason I don't know. And bypassed by the addition of another beeper wired into the reverse lights.

Lol

I'm half tempted to just rewire whole body myself from scratch!