Common 2G Problems, and What to Do About Them...

[richard schumacher]

A batch of bad valve stems? Search for that topic in the forum, there were several hundred thousand defective ones a few years ago. Or, if you got all of them at the same place maybe the installer screwed them up somehow.

[Patrick Wong]

Originally Posted by Stepho84

I believe I just encountered this on my 2007 two days ago. The car shut down while I was pulling out of the parking space at the dentist. While in traffic, the ! light and the VSC lights blared in my face. The accelerator shuddered and the car barely rode at 10mph. I eventually got into my driveway but not without someone pushing me down the street and up into the driveway.

Toyota dealer said both the 12V was dead at the hybrd battery was drained 86%. I use the car everyday and rarely have it sit for long periods of time. They recharged the batteries for me, charged $252, then sent me on my way. 1 mile away from the dealer, the battery bars dropped from 5 to 2 (even though it was JUST charged) and the check engine light turned on. As I stared at my two bars while stuck at a redlight, I noticed my engine wasn't kicking on to recharge. So, I quickly made my way back to the dealer. They're going to look into the problem tomorrow morning. I just found this thread and think it may be the same problem my car has. Ironically, my car only has 45,000 miles not 100k.

Anyone else get these symptoms with less mileage?

I agree that the 12V battery probably needs to be replaced now. However that may not be the only problem. Since the first occurrence of the driveability symptoms happened as you were leaving the dentist (and I assume the car had been parked for an hour or more before you left the dentist office) then the inverter coolant pump probably is not the issue.

A couple of weeks ago my 2004 had similar symptoms and the remedy was to reflash the hybrid vehicle and engine ECUs. I've driven several thousand miles since then without recurrence of the problem so this seems to be a lasting solution.

Good luck.

[richard schumacher]

This was part of the fix applied by a dealer when the inverter cooler on mine went wacky. But does anyone have a theory on why the ECUs would need to be re-flashed? How can firmware in flash memory get corrupted? (I'm not saying it isn't happening, I'm just wondering how.)

[dogfriend]

Originally Posted by richard schumacher

This was part of the fix applied by a dealer when the inverter cooler on mine went wacky. But does anyone have a theory on why the ECUs would need to be re-flashed? How can firmware in flash memory get corrupted? (I'm not saying it isn't happening, I'm just wondering how.)

Read-only memory - Wikipedia, the free encyclopedia

The timespan over which a ROM remains accurately readable is not limited by write cycling. The data retention of EPROM, EAROM, EEPROM, and Flash may be limited by charge leaking from the floating gates of the memory cell transistors. Leakage is exacerbated at high temperatures or in high-radiation environments.

[richard schumacher]

True enough. I would expect automotive-grade flash to be especially resistant to heat.

In the past some memory devices unwittingly used packaging materials containing high levels of radiation sources (alpha emitters) that caused bit flippage.

[dogfriend]

I think statistically speaking, the odds of memory corruption are probably very low but they are not zero. Sorta like your odds of winning the state lottery.

[alanh]

Problem: Vanity light will not come on.
Symptoms: The light located over the visor will not come on even when switched on.
Frequency: All the time.
Diagnostics: N/A
Cure: There are three conditions that have to be met before the light goes on: 1. The switch is on, 2. The visor is folded down, and 3. The cover over the mirror is open.
Comments: The third condition is what usually causes problems. If you're only turning on the light to read something, you probably won't think of uncovering the mirror.

[ny biker]

Originally Posted by richard schumacher

They will be happy to do it, if you pay them :_> Nominally, Toyota will pay for the work only during (and maybe for a short period after) the warranty period.

But! If you take the car to a dealer during the warranty period and complain about the problem, even if they cannot reproduce or verify the problem they will log it; if it manifests later outside of the warranty period Toyota will pay for it. This is especially handy for the notoriously intermittent coolant transfer pump squeal. You may get stuck paying the dealer's diagnostic fee, but that's much less than the entire repair.

When I took my car in to have the coolant transfer pump replaced, it had been making the noise every single time I turned the car off for several months. So of course it did not make the noise when I got to the dealer. But I was able to get it fixed by explaining that I know the normal sound of the pump is hmmmmmmm, but the noise I was hearing was dit-dit-dit-dit-dit-dit. My description combined with the existence of the TSB was enough for them to replace the pump.

[jonz]

Originally Posted by Patrick Wong

Problem: Car loses power. Master warning light (red triangle) appears. Brake and VSC lights may appear.
Symptoms: See above
Frequency: After car has been driven for a while, especially in hot weather
Diagnostic: DTC P0A93, Inverter Cooling Performance
Cure: Replace inverter coolant pump
Other information/Alternate diagnosis possible: This is a popular reason for Prius to stop dead, usually in hot summer weather. We've seen a sufficient number of inverter coolant pump failures so I would say that if you have more than 100K miles logged and you wish to keep your car in top condition, consider replacing this pump now as a preventive maintenance move.

Just happpened to my wife's 2007 Prius with around 15,000 miles on the odo. Fault code was P0A93 on the work order. We live in a hot climate and temp. was probably 105ish at the time of the failure. We didn't lose power for more than a few seconds. The A/C did quit working though. So the inverter cooling system pump was replaced under warranty today.

[Patrick Wong]

Originally Posted by jonz

Just happpened to my wife's 2007 Prius with around 15,000 miles on the odo. Fault code was P0A93 on the work order. We live in a hot climate and temp. was probably 105ish at the time of the failure. We didn't lose power for more than a few seconds. The A/C did quit working though. So the inverter cooling system pump was replaced under warranty today.

Thanks for writing about your experience. I'm concerned that we are starting to see a few failures where the car has relatively low miles and is only a couple of years old. This implies that a batch of faulty pumps might be in the 2007-2008 model year population...