Replaced 12v battery and fusible link, starts once, then no more

Yes, absolutely.
What leads you to believe that is NOT possible ?
It is also possible that it wasn't charged up too.

 

Bingo.

A healthy battery will easily pass that test that's a very benign load really. My almost 3 years old yellowtop did not drop a volt so you have a bad battery. It was sitting on the shelf in a low charge level for a long time before you bought it and is now sulphated.

You have to bring a voltmeter with you when buying a new battery.

Most modern chargers have recondition mode and would fix that but I would get a new battery as they are not cheap.

The dash may be throwing a Red Triangle for a second upon boot up. Real quick and does not log a code.

Very noticeable though as its the only light not lit during a boot up of the car. That's the only warning you get that the battery is to low to start the car. Its like's 11.2 volts I think. Anyway I have seen that myself when I was chasing a bad yellowtop.

I hope these measurements are done at the front jump point.

 

Yes big problem. So your not measuring battery voltage at the front jump point are you.

 

Just from the front jump points. Don't care what the battery itself reads.

Does not matter what the battery reads in the hatch only maters whats getting to the fuse box up front.
In order for the battery power to reach that box it has to go through 8 connections and a long heavy duty cable.
testing at the front jump point checks all of those at once.

Its like someone complaining there ac outlet in the bedroom is not working and your measuring that outlet voltage at the breaker box and saying I'm good here don't know what your problem is.

The fuse box under the hood is the outlet.

Charge the battery from the jump point.

The fact that it reads so low now tells me its sulphated. Hope you have a modern charger with recondition mode. I have a Mustek 4.3 off amazon works really good 4.3 amp charging so takes quite a while for the battery to to get fully charged then fully reconditioned.
Without a reconditioning of that battery it would not trust it as far as i could throw it.

You do not want to get stranded in a prius with a bad 12 volt.

 

If it took that long, it was pretty much DEAD to start with.
Those readings look good.
Is it still refusing to start ?

 

Thats not bad not sure how you gained voltage after the lights on but whatever you may have caught that battery in time. You need to get a charger with recondition mode that will fix that. But I would drive it for a few days and do my test again. Its not a fair test coming off a super long outboard charge.No battery lives at full voltage.

Put it to work...Do my test again in a few days it may be radically different. The g2 prius lives around 12.6 volts its whole healthy life. Owned my car 13 years and 3 different 12 volt battery's. That's where it lives.

 

Which code reader and or app did you get?

Here is the workup for DTC P2118 : https://share.qclt.com/%E4%B8%B0%E7%94%B0%E6%99%AE%E7%91%9E%E6%96%AF%E5%8E%9F%E5%8E%82%E8%8B%B1%E6%96%87%E6%89%8B%E5%86%8Cpdf%E6%A0%BC%E5%BC%8F/repair%20manual/04pruisr/05/2054m/cip2118.pdf

 

Throttle body butterfly stuck.

Take air cleaner off the throttle body its fly by wire it may be so dirty the butterfly is stuck. Many have failed.

Make sure the motor plug is plugged in.

Spray some lube on the return spring on the butterfly axle and grab that spring end and rotate The butterfly see if it’s free. Watch butterfly while turning. Should be smooth and return quickly.

The butterfly motor is attached to the other end of the axle some have been able to remove that little motor and grease it. Some have found replacement tb's in bone yards. It’s $1500 for a new one last I saw.

Look in the throttle bore see how dirty it is. Hold the butterfly open and stuff cut up strips of old t shirts down in the bore then soak them with carb cleaner scrub a dub dub remove the strips repeat till clean. Do not use paper towels.
Remove the 2 black hoses they pull off there plugged into the top of the tb and with t shirt strips in there spray cab cleaner in the hose inlet that's pcv input from the valve cover pcv valve.
Get all that gunk out of there.

Don't just hose the bore down with carb cleaner the engine will run really rough till its burns that up. And yes there will a puddle of oil in the bottom of the bore. Normal.

I have bypassed the engine coolant loop on mine so it has not seen engine heat all it’s life which must be hard on that little motor that turns the butterfly axle.

With coolant bypassed the tb is about 90 degee's cooler than the engine.

When you replace the air cleaner assy don't forget the 10 mm TB hose clamp under it and dont forget to plug the maf back in.

 

Stop scratching your head hoping and praying and get off the computer and go get dirty.

Do what i told you to do. take the aircleaner assy off and look inside the throttle body. It requires a 10 mm socket and a long extension bar.

I guarantee it will come back. probably never ever been cleaned. The engine will not run right if the computer cant control the throttle.

 

What do you mean by heads up display, as the Gen 2 does not have that?

Do you mean the multi-functional display (MFD) in the center of the dash?

The dark dash display is most likely a failure of the combination meter (CM) and if you are the DIY type, you can get a repaired CM with your correct odometer reading loaded, comes with a lifetime warranty from @Texas Hybrid Batteries. The cost is ~$150, and they will give you $75 back for your old broken CM.

Given both are out, it could be something else, so retrieving the diagnostic trouble codes (DTCs) will help with further diagnosis.

An afterthought, do you have power to other things like the hazard lights, headlights, interior lights, door chime when open with the key in the slot?

 

You NEED to get over this obsession with the battery posts.
A bad connection there will NOT be selective about what current it allows to pass.......causing some things to work and not others.
IF those connections are clean and tight, they can be made better later.