Is this a 4 cylinder?

To me, this sounds like a charging issue with the alternator being the principal culprit. Cable connections would be secondary.

 

It is a 4 cylinder

 

Ground G1 is where the other end of the battery negative cable is normally attached to.

 

The G1 ground is there but on mine the cable off the terminal splits. One side goes to the G1 and the other is grounded in the picture I posted before. I think its supposed to be on the transmission case but I'm not sure. I think it might have gotten moved.

Yr point about the alternator is well taken. Four months ago I replaced the battery and then the starter.

 

So I could really use some help! I just went out and sanded all the corrosion off that second battery ground (pic above). I think when I took it to Firestone they just slapped it there because the starter they put in blocked access to where it was grounded on the transmission. In any case, there was a lot of corrosion and I removed it.

Hooked up the jumpbox. Had trouble getting it to create a circuit. Probably just corrosion on the strut mount where I grounded it. Moved the box's ground to frame and then checked with a volt meter. 12 volts! Current was flowing. Let it sit for 5 mins. The interior lights came on when I opened the door, so good sign because they were dead before. Tried to turn it over. The & percent on the jumpbox (which is old) leaped to 70% and then there was a click/pop sound like maybe the started tried to turn once and then nothing. Totally dead again. Recharged the box and tried to connect it but couldn't get a circuit to form with battery (volt meter stuck on .2/.1). Connected phone to box's usb port and it started charging, so I don't think the box is broken.

Any ideas what this could be? Battery and starter were replaced 4 months ago. Could it be a bad battery? Could it be the alternator? Would the alternator cause the jump box not to charge the battery?

Could that second ground being in a different place (given that it does have another, but smaller ground--which is good, I checked) could cause all this?

 

T3 is where the other end should normally connect to in this photo.

 

It seems like either location would be OK because they're both substantially on the transmission case. (As long as they aren't loose/dirty/corroded)

This is a long shot, but it's possible the cable is corroded & fraying inside it's own rubber insulation (maybe at the low point where moisture might collect inside the insulation).

 

Ok, that's helpful. It's definitely grounded somewhere else now. And the connection was super corroded. So hopefully it was just that.
But the cable is a little worn and has frayed a bit because of being connected and disconnected.

The cable would make sense too right, if with the jump box it was making a circuit and then not all of a sudden?
Just having one of the two grounds loose wouldn't cause a circuit not to form? idk

 

Tried to have a friend jump it and nothing. After 10 minutes of letting his car run, no interior lights, no dashboard, nothing.
My next move is a tow truck to Firestone?

 

Moisture getting inside the insulation to cause corrosion & fraying might be happening on several wires, who knows? If the ground to the transmission is flaky, then the ground to the fender sheetmetal has to take all the starter current (through a smaller wire). And then the ground current still has to get from the body to the starter, through whatever connections it can find which might be several small wires in the wiring harness for sensors or switches. Cars that don't have a split negative battery cable would instead have a heavy ground cable bridging across an engine mount or something like that.