Intermittent no-start

I have a 2001 Volvo V70, and intermittently it won’t start. I can’t seem to reproduce the problem, but it happens about every 6-8 times I drive somewhere in my car and go to leave. The symptoms when it happens are:

1.) The dome lights, dash, everything clicks and goes dark.

2.) A simple ‘jump’ from another car fixes it and gets me on my way.

3.) It happens in both wet and dry weather alike.

Here are some things I have noticed or have done:

1.) Battery is new, and tested fine- but did show a slightly low charge

2.) Alternator tested fine by local auto parts store.

3.) The dash dims with loud stereo (stock) or blinking of the hazard/turn signal lights.

4.) No obvious short circuits of the battery.

Poor (resistant) connections, of battery cable terminals, don’t allow charge to get into the battery. Other wire connections might, also, be causing voltage drops between the battery and the inside of the car.
Disconnect battery cables and wire brush the contact areas of cable terminals to posts (battery terminals). Check the power supply wires (for voltage, resistance, connections)from the battery to the inside of the car.

Thank you for the feedback, here are some additional things I have already done:

1.) Ensure the battery contacts/wires are clean/secure.
2.) Test battery voltage under the hood (my battery is in the trunk)
3.) Checked/removed/reinstalled the battery to check for secure wiring or faults.

With the engine running, check the battery voltage, in the trunk. The voltage should be between 13 1/2 to 14 1/2 volts. Check the voltage to the fuses. The voltage should be the same as the battery, or alternator, voltage.

Check resistance of ground cables and make sure ground connections are clean and tight at BOTH ends,

I was out of town all week, but went back to the car first thing Saturday morning. I’m happy to say I found the ground cable attached to the battery was ok, but the end attached to the chassis was loose. None of the symptoms are present, and the car starts/runs great.

Thanks for getting back to us. Good to hear it works.