Power Steering question:

yes, with tech stream

 

The power steering likely is electric.
So I would "guess" at one of the batteries.
If you still have the original HV battery, 16 years old, your time might have run out.
But check the 12 V first.

 

That's not a guess; every Prius's power steering is electric. It's powered from the 12 volt system in Gen 1 through 3, and I'll say also 4 unless someone tells me otherwise, and of course whenever the car is READY that power is coming from the high-voltage system via the DC/DC converter.

There are a number of different issues the steering ECU can report. If you ask it what it's reporting, it'll tell you. Generally where I'd start.

 

Yes, you have made it abundantly clear on previous threads that YOU would blindly start chasing reported codes.......WITHOUT first checking the 12 V system integrity.
And I have tried to point out that is not a good way to proceed.
Alas, it hasn't sunk in with you yet it seems.

 

You've made clear endless times that you hold that opinion, and that you consider knowing what the most specific piece of evidence available to you means to be "blindly" chasing something.

There's something there that isn't sinking in with you either. But probably other people reading these threads are able to catch it, and that's good enough.

 

The power steering on a 2005 is definitely electric assist.
How would a HV battery problem cause a power steering MIL? (esp without turning on a bunch of other lights first)
Yes, testing the 12V battery is a good idea early in the diagnostic process.
Even if the 12V is bad, I would still scan all the vehicle systems for codes with a capable scantool and document them. The light is on- there should be a code. Might be related to (or explained by) a weak 12V- or not.

Posted via the PriusChat mobile app.

 

I know that this is a waste of time but...............

Good troubleshooting technique is pretty much universal no matter what the equipment in question IS.
The first step is to LOOK for physical damage.
The second step is to verify proper operation of the power supply.

Telling people to ignore either or both of those steps is giving out irresponsible advice.

And yes, I will continue to call you on it every time that I notice that you have jumped PAST the power step and gone directly to codes produced by a computer that might be starved for power and not working right.

 

I know that this is a waste of time but...............

Nobody is saying to ignore checking the power supply. Usually, that is covered in the post so no need to rehash.

You also seem to fail to comprehend that for those gremlins you so infuriatingly insist are a problem, the voltage needs to be well short of 8.5V even more like 5V or less.

You are helping no one with the incessant badgering/bullying of posters. I can recall more instances of where posters have succumbed to this advice, for it to be just wasting their time and spending a good wad of cash on a new battery which made no difference than I can where it was the problem. Where a bad 12V supply is obviously the problem it is not ignored – appropriate advice to check the 12V is given.

More specifically in this case, the power steering is powered by the 12V bus when the car is READY. For that to happen the 12V has been good enough to get the car to READY. At this point the 12V is powered by the DC/DC converter. These are points already made by ChapmanF in his earlier posts.

Your assertions are irrational.

 

And your assessment is inaccurate.

It is a considered opinion, based on about 50 years as an Electronics Engineering Technician.

Take it or leave it but don't argue with me that it is EVER good to ignore the power supply and just jump right in chasing codes.

Especially if there are several present that seem to be unrelated.

I am trying to be helpful. What are you trying to do ??