Half full battery indicator, electric motor running after shutoff. HELP!

The only thing I can think of that would be in that vincinity would be the inverter. Your traction battery maybe OK. When was the last time you had the inverter's coolant stuff? Is this what you'll be doing at 120K checkup?

 

I'd recommend calling Re-InVolt and ask to describe what happened. Right now, I can't tell.

Bob Wilson

 

Among other things, yes. And I assume that they will check for error codes and see what the warning was all about.

I started it up, ran it a few minutes and turned it off this morning, no problems, no post shutoff running. If I am not mistaken, the pink coolant is essentially antifreeze. I should be able to check it on a normal specific gravity tester, no? I might as well, nobody is open today anyway.

 

There's bound to be somebody out here who knows the Specific Gravity of the pink coolant. Maybe somebody who posts charts all the time...

Bob?

 

Sorry, I can't help much in this discuss. I swapped my inverter coolant at 53,000 miles because I opened the wrong drain plug . . . happy accident?

I have a bunch of high temperature thermostats and am thinking about having the Toyota shop in Decatur replace the thermostat and coolant.

Now Doug has been an advocate of having the brake fluid tested for water and I was planning to wait for pad replacement, about 50-70,000 miles from now. But this again is one of those cases I would prefer to let my Toyota service center handle.

I'm more concerned about the pH of the coolant than anything else. There have been a number of reports of clumpy stuff in the inverter coolant loop. My concern is the coolant pH may have changed enough to begin forming aluminum salts. This would be bad.

When I'm confident about the prospects, I'll combine inverter coolant change with the pump swap-out.

Bob Wilson

 

Hello fireclown, and sorry to hear you are now experiencing something weird. I'm no expert but have been told I have plenty of intuition and common sense troubleshooting problems. The main thing that hits my mind in your case is the fact that the HV pack is unusually draining overnight, and of course you heard the vibrating sound a couple times up front after shutting down. When you shut down, the main HV relay in back (HV battery pack) opens, thus opening the circuit. The sound you heard and the fact that the SOC dropped overnight tells me that it may be a stuck relay keeping it connected to the inverter thus draining it, plus the fact that after shutdown the ECU's are all mostly inactive and if HV were still present at the inverter, who knows what state it would be in without an active controller. It may be trying to drive MG1 or 2 for that matter, but logic says this is highly unlikely without the ECU clock signal that the inverter needs to provide 3 phase power properly. This is only a guess of course but what I would do next time you hear the noise after shutdown is remove the negative of the 12V battery real quick and see if it goes away. Try to remove it for only a short time (like less than 1min.) so you don't erase any DTC's that may be stored. Then quickly re-attach the 12V battery. If the noise stays during the time you've removed the 12V system, it almost surely is a "stuck relay" since that HV relay needs the 12V system to switch. If the noise goes away and then comes back with the 12V re-attached, then there may be something else ECU, inverter etc. causing the problem. One other thing to do when you think the relay is stuck is to lightly tap the trunk floor to perhaps un-stick it. You should also be able to hear the "clunk" of that relay right when switching the ignition switch to off. This is louder in the GENII's but you should be able to hear it if it's functioning properly. Just some ideas..

 

Is it possible you've just never noticed the noise before? Most Prius will run the brake pump for a few seconds after shutting the car off. It makes a little vibrating electric-motor sound for a few seconds. Unless what you're hearing is something different.

 

We own both GEN1 and GEN2 (03 and 06) prius' and I know what you mean about hearing noises after shut down in the GEN2, but I have never heard anything from the GEN1 after shut down. It is always quiet after shut down. I suspect something is going on there.

 

I just got the car back from a major servicing, and here is what they told me.

There was an error code from the steering transducer. They checked it and found nothing wrong, and we are treating it as a glitch. I also had a belt that needed replacing, and there was some crud in the manifold that needed to be cleaned. Not too shabby for an old car.

The symptom has yet to occur again. I don't know what to think about it, but for now I'm willing to keep on driving. Fear not, I'll post up if there is a re-occurrence.

 

The steering box assembly (transducer) is another area in gen1 prone to failure and would cause a vibration, but I just don't know about even after the ignition switch is off. Good luck with it, perhaps the major service checking it -they fixed it..

 

They mentioned that the error code had to do with the transducer. They looked at it, and didn't see a problem. It's been a week or more, with no further problems, so I'm going to hope for the best and hope that it doesn't happen again.