2008 prius will only stay in ready mode for 5 seconds

any trouble lights?

 

Even though it sounds like the engine started it did not. The ECM is trying to start the engine by spinning it using the electric motor/generator, but it does not detect any power from the engine within the time specified, so it aborts the attempt. If you scan for codes you may find a P3190, P3191, or P0A0F.

The bad news is, that there is a finite number of times you can do this before the hybrid vehicle (HV) battery runs out of juice, so you need to fix the problem before trying to start the engine again.

There is a scenario where the car goes dead while driving which is caused by the AM2 fuse blowing due to the inverter coolant pump shorting out. You could test out this possibility by disconnecting the inverter pump and then replacing the AM2 fuse. You can disconnect the inverter pump by unplugging the connector shown in the attached photo.




Location of the AM2 fuse:




Location of the inverter coolant water pump:




You might also be able to check the pump by putting the car into IG-ON (two presses of the power button without your foot on the brake pedal) and looking into the inverter coolant reservoir to see if you detect coolant moving.



I hope some of that helps.

 

you can get the trouble codes read at a dealer, hybrid shop or buy your own

 

With the fuse in place or removed?

The pins don't look good, but hard to tell just by looking, particularly as the fuse itself is out of focus. If you want to be thorough, you could test the fuse with an ohmmeter, but really, just replace it ensuring you have disconnected the inverter coolant water pump beforehand. I would also inspect the slot into which that fuse goes, and make sure it was clean of any corrosion and the like.

I'm confused by this statement. What do you mean by, "between the time I brought it home and the time it was driven next". Has the car been driving since it just suddenly stopped while driving?

If there are lights on the dash now, you should get the car scanned (using a capable scanner that can read all of the 11-14 computers). You could then post the results of that here which would be most useful.

 

152758_P2102_-_Throttle_Actuator_Control_Motor.pdf