I have 2 cars that have been sitting for abit, which ran fine when I parked them. I bought a new battery but neither car has any power what so ever, what is my best course to find the problem?

Verify with a voltmeter, check battery cables, connections, power in and out of fuses?
Headlights work?

Verify with a voltmeter, check battery cables, connections, power in and out of fuses?
Headlights work?

Good volts at batt, cables look OK, connections clean at batt, not sure which fuses to check or how. No headlights, no power to dome, fans etc.

Have seen a few posts saying something with solenoid on starter? Could this be something? Would that cause no power at all anywhere?

Local auto parts stores have a 5 dollar test light with an alligator clip that clips to ground, then you touch the probe to each side of fuses or each end of a wire/cable, you can't hurt anything unless youu touch probe with ground or other wire.
First test with light should be at Battery to verify operation, and battery power.

Local auto parts stores have a 5 dollar test light with an alligator clip that clips to ground, then you touch the probe to each side of fuses or each end of a wire/cable, you can't hurt anything unless youu touch probe with ground or other wire.
First test with light should be at Battery to verify operation, and battery power.

Did try using volt meter on fuses connecting to each side and did get some minor readings not sure what they should be if that works at all or if I need this light tester you are talking about. But I also tried same method on the car that runs and couldn't get any readings so who knows.

Guy at parts store said to check the main line to the fuse block to see if there any burn out there, I traced as far as I could reasonably see and can't find anything... is there an easy way to check continuity in those lines? Have tried putting the meter on it but I can't get it to register anything even if I'm only a few inches away and can see there is no break.

DO NOT connect to each side of the fuse,
One to ground and then one side of the fuse, then the other. A good fuse will be zero volts if connected to each side.
Any question, Remove each fuse and visually check, REMEMBER where it came from or you may introduce a new problem.

If you installed a new battery in the car and still no lights it sounds like a bad ground or bad battery connections. Make sure you clean them with a wire brush. After you connect them and they are tight, with your test meter on ohms you can check the connection. Put one lead on your battery post and the other on the connector. You should see .2 If the number is higher your connection is not good enough. You can also check your ground this way. One lead on the negative battery post and the other on bare spot on the frame.
Good luck!

The big Positive wire goes to Starter, then maybe fuses, fusible link, Its odd 2 cars did the same thing,
Sabateurs?
What is the Make and Model of the Cars.

The big Positive wire goes to Starter, then maybe fuses, fusible link, Its odd 2 cars did the same thing,
Sabateurs?
What is the Make and Model of the Cars.

A 79 chevy malibu and a 90something dodge spirit 96 I believe

That's what's really getting to me it's the two cars with the same problem.

As far as I can tell all fuses (that I can find, I don't see any in the lines themselves) are fine, connections look clean and tight, its got to be in the wires themselves somewhere then?? I traced a few of them and they all looked solid.
A guy at parts store said he had a guy put a batt in backwards once and it blew a line like that. While I don't think I did this, where would I look or is it random? I am just trying to narrow it down.

First test should be at battery. If it is an analog meter(with a needle), it will peg the needle down, below zero. Reverse leads and needle will read upwards, should read about 12
Volts.

First test should be at battery. If it is an analog meter(with a needle), it will peg the needle down, below zero. Reverse leads and needle will read upwards, should read about 12
volts.

It is digital and reads 12.4V

I can only think a wire has been left disconnected, Verify Power between the HOt from Batter Post to Block Ground(any metal on Block, and Chassis.
The Large Red(positive)goes to staryer and can have wires going back to main feed of fuse block or through a fusible link.
Check at Battery, Then Fuse Panel(in and out of fuses).
Check at Starter, Large Positive to ground, should be around 12 volts(Battery voltage)

I can only think a wire has been left disconnected, Verify Power between the HOt from Batter Post to Block Ground(any metal on Block, and Chassis.
The Large Red(positive)goes to staryer and can have wires going back to main feed of fuse block or through a fusible link.
Check at Battery, Then Fuse Panel(in and out of fuses).
Check at Starter, Large Positive to ground, should be around 12 volts(Battery voltage)

Sorry it has been a couple days I will check this soon, thank you all for input