SSC50P like a new car!

:angry: YES!
This has been a most disappointing 'upgrade' (wish I'd never had this recall done).
Actually, I believe I'd already had this (or similar?) recall complied with earlier.

Shortly after the media was running with the story of some Prius stalling while driving (IIRC, this was supposedly due to folk not taking in the Prius for yet an earlier recall [ECU flash update] which should have prevented any on-road stalling). In any event, I mentioned to the service that I believe I'd already had this recall (ECU flash) completed; nevertheless they scheduled this latest and I had the "SSC 50P" completed on 14Nov05.

Performance is clearly degraded. Off the line, I would usually accelerate briskly (okay, I keep it floored) until I reach the desired speed than back off and coast/feather to maintain speed. (Many moons ago, this was deemed the most efficient way to maximize mileage [still true?]). Unfortunately, after this 'upgrade', there is always a delay and the acceleration is not as hard (curve less steep). Additionally, there seems to be an even greater lapse when slowing/coasting and then trouncing the accelerator; this is most disquieting and creates a feeling of less safety.

I've driven well over 100K miles between my Prii (~37K on the '04 [~98K on '01]) and was quite familiar with their capabilities and handling. Lately, I'm less confident when I need the car to quickly respond (e.g. passing or avoidance manuevers).

I'd recommend others hold off on this 'ECU flash', (especially if you've already had the earlier and are comfortable/confident with results) until more information is known. This, of course, will also give your dealership more experience with this procedure. ...I'm wondering if mine was properly performed.

Collect more info; consider your options; Good Luck!
--Stephen

 

There's *always* a lag, because the initial push comes from the
battery [limited to 100A / 20kW, do the math for horsepower] and
before the engine can produce the additional power required, it has
to spool up to a high RPM, and that's still done gently because the
motor-controlled throttle cannot really *snap* open and the ECU
doesn't really want to do the huge-enrichment thing that would be
required along with anyways. Understand your system and plan ahead.
.
Now, some of tomdeimos' observations may have some coincidental
relationship with colder weather. I'm noticing that various battery
currents [both in and out] seem to have higher, longer bursts while
the car is still cold -- such as charging up to 7 or 8 greens for
no apparent reason, or letting me push 50 amps in stealth for brief
periods before the ICE is actually warmed up and in stage 4. I
wouldn't doubt that this is actually *stragegy* for getting the HV
battery warmed up faster, since even with plenty of cabin heat it'll
take a while for it to reach back there and go through the ducts.
So more current == more internal cell heating, possibly at the
expense of a little efficiency but long run, probably better once
the pack is at a better temp.
.
Oh, and no, I don't have SSC50P yet. May never, in fact.
.
_H*

 

I have to say that we can figure this out. First we need to collect some data. These anecdotal posts are nice but the only thing that they say is we need to collect data.
#1 if you have been collecting data on your actual MPG before the switch you are in. Now you need to keep collecting data.
#2 The USWS collects data on average temp data high and low we need to corollate that.
#3 We need to collect data after the flash. Hopefully we need Summer, Winter data, depending on when you got the flash.
#4 we need to compare the data to see if there is a difference
some variable that come to mind that we might whish to control for: driving style description, i.e. "Totally coast and glide using the energy screen, ScanGage, CAN View, and anything else I can get ...Prius Master", "Milage improving still using the consumption screen.... Intermediate driver", "Milage OK this is a new car and I am just breaking in the car I am still using the Energy screen and am amazed by energy transfer in this car".... Prius beginner, "I am dazzled by the information, have not finished the owners manual, Wow".... Prius novice.
#5 after driving style there are other variables, like radiator screen, engine insulation, block heater, use of alternative data source, i.e. see above CAN View etc.
#6 you supply what ever we need to control for.
Then we collect the information and compare it.
I will be getting my flash at 25K, with oil change etc and will keep folks posted. I would suggest we need a few months before and after the flash, as well as past history if we have it.

 

I may have more miles on my car since the SSC50P flash than most, since I took a 2000 mile roadtrip on the car right after the flash. Here's what I noticed.

Initially, (first 1000 miles), the car kept the battery near a full SOC, something new. With highway driving it would almost always stay green. In the past it was normally around 4 bars. The car did seem to get a bit lower mileage (about 3mpg lower) and a bid slugish.
At about the 1000 mile point things got back to normal. The SOC went back to the typical 4 bars, mileage went back to normal, and performance seems normal now.
Of course this week winter hit with a vengance and it is now 2 degrees out and I'm driving in snow on Blizzaks, so I can't really judge anything any more.

My best guess is that after the flash, the car goes through some sort of battery conditioning or gauging routine, then settles down to normal.

That''s how it worked on my car, ymmv!

 

sORRY BUT WHAT IS SSC50P?

 

I would call it a 'learning period' rather than a 'break in'.

It's not unusual for modern cars, not just the prius, to 'learn' patterns in engine management, and after a 'reset' of the computer they have to relearn them.

Some modern cars even have adaptive transmissions that 'learn' your normal acceleration/shift patterns.

It's to the point where you can get in two identical cars that have been 'trained' by different people, and they behave very differently.

With the Prius, juggling all the variables of ICE/motors/battery/brakes, it's a complex equation and would logically take a while to settle down.

 

how do you get this info out of your car?

 

SSC-50P is Toyota's answer to complaints and symptoms of ICE failing to start. Also I think they folded in a fix for a false DTC regarding the MG position sensor.

50P encompasses an update to firmware in the HV ECU and ICE ECM, as well as sealing a sensor connector with dialectric grease.