ABS issue, Beeping and many dash lights

I also think that you have multiple issues with your car. The first thing you need to do is buy a better scantool that can communicate with all the ECUs in your car. Take a look at the link below, which reviews a number of different scantools for a Gen 2 Prius.https://priuschat.com/index.php?threads/232741/

Posted via the PriusChat mobile app.

 

As far as the codes from the brake system, that system has a way to get the codes without a scantool, and she did that.

Blink (a/k/a Flash) Codes – How to. | PriusChat

Now if she did have a better scantool, she might also get the INF codes that go with her C1241, and it might be helpful to have those, as dolj suggested in #10.

Also, the better scantool would get the code(s) responsible for the red triangle light, which would be worthwhile to have.

 

What do you think about the mini VCI techstream? When I used it a while ago, it seemed pretty accurate.

 

TechStream is what Toyota dealerships use for diagnostics, so it is the gold standard.

Posted via the PriusChat mobile app.

 

Is the old pump bad and how did you test for it?

 

Now that you have your car running I suggest you get the following items for “next time”:

a Mighty Max 35Ah 12 v battery from Amazon. Much cheaper than any other 12 v bat and pretty easy to install - terminal clamp bolts thru the battery post holes, and some wedges to hold it in place

a cheap smart charger - Foxsur from Amazon

keep the spare battery charged with this

Mini VCI Techstream from eBay. It’s hacked so it never expires. Of course don’t try to log on to the Toyota Techstream website

get the components and build a grid charger. This will enable you to charge your HV bat if you have an issue with repeatedly failing to get the engine running. Cost will be under $100

This way you’ll have a few things you might need next time a problem crops up

congrats on changing the coolant pump. If you can do this, the above items are easy. Just be very careful around electricity

 

You don't really need to be buying a battery now for something that might happen 2-5 years in the future.

 

The ABS NO. 1 & ABS NO. 2 relays are located in the engine room fuse box. They are the green rectangular ones, one at the top, and the other at the bottom right.

Here is a link that will show you how to test a relay.

How To Test An Automotive Relay At Home | Mechanic Base

It might be time to find a way to read the HV system codes you're not seeing just so you can get the full picture. A few posts in this thread have already mentioned the scanner review thread which contains a few options.