Main fuse keeps popping, can you help?

I just rebuilt the entire bike and may have assembled some wiring wrong, dunno. It's 78 KZ1000. What I figured out so far is that both turn signals and the hazard lights will cause the main 20 A fuse to pop. It will run fine and all other electrics work until I hit turn or hazard.

This will happen whether the motor is running or not.
I have replaced the flashers and checked all the bulbs are working.
The wiring going in and out of the main fuse gets warm while on.
Inside headlight bucket there are 2 large, multipin connectors. The smaller one gets warm.
These warm parts happen while idling and NOT using the hazard or turn signals. Maybe some warmth is normal?
Any ideas what's causing this?

I also cleaned the paint off the engine ground connection and checked resistance from engine to negative battery terminal (none).

This is my build thread if you wanna see the project:
kzrider.com/forum/11-projects/398465-nel...hter-build?start=460

I'm really at a loss for finding the problem. Wondering if I should rewire the turn signals completely.

I'd remove the main fuse, and using a bulb holder in it's place, with the engine off, put a 12 volt bulb in the socket or holder, if the bulb lights up, there's a problem, now to go through, disconnecting circuits, until the light stays out. This is where the circuit problem is.

The front turn signals are usually also running lights, so it's possible you've changed single filament bulbs and/or sockets now in the wrong place in the circuits.

I had the same problem. Turned out to be a pinched wire but only one side was effected. Must be before the switch or in it.
Steve

Can't help, but will say the fuse and wiring near there run warm to hot even if everything working, so that part is not indication of a problem.

Wiring getting hot and fuses popping is too high current and / or short circuit fault,

You may have two problems here, firstly a dead short on the indicator circuit popping fuses instantly. Short circuit = live finds a low resistance 'earth/ground fault , and a bigger current flows melting the fuse within a second or two - the resistance of the bulbs/load limits this current in normal use)

Secondly, bad wiring causing the main ignition power feed to get warm - shouldn't ever happen. Block connector in headlight getting warm points to a dodgy connector there, or bad ignition switch or fusebox. Old z1000 fuseboxes can be a problem here.

Probing this with a voltmeter expecting it to be down a volt at the end of the dodgy wire won't happen, as you need to draw a current through the high resistance of the bad wire/connection, more than a meter will do.
So a dodgy live circuit would test meter at perfect battery voltage, but when connected a bulb or other load would glow dim.

Checking resistances with a meter on the circuit from battery to fusebox, to igniton switch and back to fusebox (the main fuse powers all the others on the later z1000) might be where the problem is. Too much current draw probably caused by caused by a voltage drop (resistance) somewhere in circuit. It gets hot as the load needs to draw a higher current to compensate for reduced voltage. Heating in a wire is proportional to current squared, so a small difference here makes a big difference in wires getting hot.

Do the main wiring heating problem first , then look for indicator fault.

Yeah I was thinking it might be two diff problems. Thanks for the tips. That gives me some things to try.
While the whole bike was apart I cleaned all the connectors and checked resistance of all the wires and found no problems, so it's surprising to have these issues.

By the way, the fuse doesn't pop instantly when I turn on the signals. They will flash for maybe 5 to 20 seconds, then the fuse blows. Does that mean anything?

Yes, that means rather than a dead short, which would pop a fuse in a fraction of a second,
the fuse is probably heating up due to too high a current. Alternatively you have an intermittent fault - although the same time period taken to blow the fuse each time makes that unlikely. Most indicator circuits are 10 Amp fuse and use less than l half this current.

Test you resistances from flasher unit to bulb holders with bulbs removed and indicator switch selected, and in and out of fusebox. Also your ground connections, I often put a spare battery -ve ground at the front and back of the lighting looms as well as the main earthing point. Freshly painted or coated frames can need attention to the earth point.

What I said about the later z1000 fusedbox , if yours is the earlier 3 way then they are the same as on the 550's and are more reliable I think. The earlier 3 way have indicators powered from the main 20A ignition fuse.

I like to eliminate parts of circuits when testing, so you could experiment just by disconnecting one winker at a time and see if you can narrow down the fault. Then use a jumper wire (with an inline fuse of 20a ) from the flasher unit to the indicator, temporarily replacing that part of the circuit. Also do a'wiggle' test with a test lamp, sometimes dodgy wiring meters ok but only when it is moved it starts playing up.

A high resistance bad connection in the ignition switch, indicator switch, fusebox or defective wire somewhere in the loom won't show up without an Ohmeter. There are also staples buried withing the loom that crimp the earth returns together, sometimes these can be a cause of bad connections. Your block connector getting warm here is a the clue to follow.

As well as your blowing fuse problem, you will probably notice that all the lights and instruments are much brighter when you have traced this.

wow! great info, thanks! i have a lot of work to do.