Can Prius Computer be Adjusted?

rgrafstein · 02-28-2006, 07:26 PM

Is there a forum specifically for this issue:
The gas engine in my 2005 Prius comes on in the garage even when the battery shows almost fully charged and I haven't stepped on accelerator. And I think that engine kicks in too soon when I'm driving gently down the street. I will be bringing Prius in for its 10,000 mile servicing in a few weeks. I called the dealer and was told NO ADJUSTMENTS TO THE COMPUTER ARE POSSIBLE!!
Does anyone know if this is completely true? Is there some way to get them to adjust it? Can I do it myself? How do I know if its working "normally"?

Rancid13 · 02-28-2006, 07:31 PM

The gas engine will come on and shut off when and where the car wants it to. When you start the car, whether the battery is fully green or not, the engine still needs to warm up, even if only for a few seconds. Especially if you have anything on in the car that might use up juice-climate control, audio, light, etc. This is how the Prius is supposed to function, there's nothing wrong with the car whatsoever and I wouldn't worry. Short of self-installing an EV mod to the car, there's not a lot you can do about it. Maybe look into that if it interests you...

infohwyguy · 02-28-2006, 07:33 PM

Quote:

Originally posted by rgrafstein@Feb 28 2006, 08:26 PM
Is there a forum specifically for this issue:
The gas engine in my 2005 Prius comes on in the garage even when the battery shows almost fully charged and I haven't stepped on accelerator. And I think that engine kicks in too soon when I'm driving gently down the street. I will be bringing Prius in for its 10,000 mile servicing in a few weeks. I called the dealer and was told NO ADJUSTMENTS TO THE COMPUTER ARE POSSIBLE!!
Does anyone know if this is completely true? Is there some way to get them to adjust it? Can I do it myself? How do I know if its working "normally"?

[snapback]218269[/snapback]

Can't be totally sure if your Prius is working normally, but I suspect it is. There are many factors that would cause the engine to start, aside from the battery needing charge. By the way, unless you have an EV switch, your engine will always start about ten seconds after turning the car on. This is totally normal. It's also much easier to keep the engine from starting while driving gently if you have an EV switch and put it in this mode... but still, it takes a very light touch to prevent the ICE from starting.

Rick S

Presto · 02-28-2006, 07:44 PM

Another thing to add is the Prius will start the ICE immediately if you have the front defrost on. I'm pretty good at making sure it's off when I stop the car so I can engage EV mode on the next startup.

seasalsa · 02-28-2006, 10:01 PM

Since you failed to mention your location, I am assuming you live in a colder climate. If so, just wait till the weather warms up and your problem will solve itself.

galaxee · 02-28-2006, 10:06 PM

no adjustments like that are possible. the ECU program is a complete unit and cannot be tweaked to user preference.

the car works to provide good fuel economy AND low emissions. the "low emissions" part is what's bugging you. but the car does what it has to do to warm up the engine and the cat in a timely fashion for emissions. nothing you can do about it.

in short, they're not lying to you.

rgrafstein · 02-28-2006, 10:34 PM

Quote:

Originally posted by infohwyguy@Feb 28 2006, 04:33 PM
Can't be totally sure if your Prius is working normally, but I suspect it is. There are many factors that would cause the engine to start, aside from the battery needing charge. By the way, unless you have an EV switch, your engine will always start about ten seconds after turning the car on. This is totally normal. It's also much easier to keep the engine from starting while driving gently if you have an EV switch and put it in this mode... but still, it takes a very light touch to prevent the ICE from starting.

Rick S

[snapback]218275[/snapback]

THANKS A LOT TO EVERYONE FOR YOUR PROMPT AND USEFUL RESPONSES. It never occured to me that warming up the engine and the catalytic converter would explain the early startup I''ve noticed.
ABOUT THE EV SWITCH: is this something that I would have to install myself? does Toyota not provide or install it? would it invalidate my Toyota warrantee?
Thanks again,
Roger G

KTPhil · 02-28-2006, 10:47 PM

Search on "EV switch" and you'll find the many answers to your questions. It is one of the most popular topics here, along with running out of gas (sheesh).

By the way, I've never seen an "adjustable computer." Well, I guess a slide rule qualifies...

jbarnhart · 03-01-2006, 03:34 AM

It's important to understand the Prius is not an electric vehicle. In fact, ALL of the motive power comes from the ICE! The battery and electrics are there only to assist the engine make the best use of its torque and fuel efficiency.

When you take off from a stop, the ICE will turn on. It's the prime mover and it is needed to add its power to the wheels. In fact, the best fuel efficiency comes when the engine drives the wheels directly. Any time the electric motor is used, you are losing efficiency from the losses generating, storing, and using the electricity.

The Prius is a gas powered car. The electrics merely help it run in its most efficient range. Don't try to drive on the electric motor all the time!

tomdeimos · 03-01-2006, 08:17 AM

The car can definitely be adjusted. Mine is completely different since the SSC50P update. Before I had trouble staying electric. Now it is easy and I can do it even on some hills where it never happened before.

Every computer update has tweaked things a bit differently from what I read hear.
Only problem is we don't get to choose which update to get!

02-28-2006, 07:31 PM	#2
Rancid13 Cool Chick with a Black Prius Join Date: Aug 2005 Location: Los Alamitos, Orange County, CA Posts: 2,455 My Car: 2006 Prius Model: Package: #8 Thanks: 0 Thanked 0 Times in 0 Posts Friends: 2	The gas engine will come on and shut off when and where the car wants it to. When you start the car, whether the battery is fully green or not, the engine still needs to warm up, even if only for a few seconds. Especially if you have anything on in the car that might use up juice-climate control, audio, light, etc. This is how the Prius is supposed to function, there's nothing wrong with the car whatsoever and I wouldn't worry. Short of self-installing an EV mod to the car, there's not a lot you can do about it. Maybe look into that if it interests you... __________________ Jennifer 2006 Black Pkg #8 w/bisque leather "Max" (Prius Maximus)

03-01-2006, 03:34 AM	#9
jbarnhart Senior Member Join Date: Jan 2004 Location: Santa Clara, CA Posts: 629 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 1	It's important to understand the Prius is not an electric vehicle. In fact, ALL of the motive power comes from the ICE! The battery and electrics are there only to assist the engine make the best use of its torque and fuel efficiency. When you take off from a stop, the ICE will turn on. It's the prime mover and it is needed to add its power to the wheels. In fact, the best fuel efficiency comes when the engine drives the wheels directly. Any time the electric motor is used, you are losing efficiency from the losses generating, storing, and using the electricity. The Prius is a gas powered car. The electrics merely help it run in its most efficient range. Don't try to drive on the electric motor all the time! __________________ Super White '06 pkg 8 born on 1/19/06 side moldings :: 3M clear bra :: BT Tech brace :: Comfortreds Coastal EV mod :: Curt (U-Haul) Hitch :: mudflaps :: NuShield

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
07 Prius Computer Death	hybridbrian	Gen II Prius Technical Discussion	20	10-24-2007 09:31 PM
Prius computer capabilities	lenjack	Gen II Prius Technical Discussion	4	01-02-2007 11:42 PM
Buy The Prius Computer!	Prianista	Gen II Prius Main Forum	5	07-07-2006 07:51 PM
Prius Computer OS?	LarryRacies	Gen II Prius Main Forum	6	03-30-2006 11:54 PM
Prius Desktop Computer!	maf	Gen II Prius Main Forum	12	10-24-2005 06:03 AM

02-28-2006, 07:26 PM	#1
rgrafstein Join Date: Feb 2006 Posts: 2 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Is there a forum specifically for this issue: The gas engine in my 2005 Prius comes on in the garage even when the battery shows almost fully charged and I haven't stepped on accelerator. And I think that engine kicks in too soon when I'm driving gently down the street. I will be bringing Prius in for its 10,000 mile servicing in a few weeks. I called the dealer and was told NO ADJUSTMENTS TO THE COMPUTER ARE POSSIBLE!! Does anyone know if this is completely true? Is there some way to get them to adjust it? Can I do it myself? How do I know if its working "normally"?

02-28-2006, 07:44 PM	#4
Presto Has his homepage set to PC Join Date: Mar 2005 Location: Vancouver, BC Posts: 1,257 My Car: 2005 Prius Model: Package: B Thanks: 0 Thanked 4 Times in 4 Posts Friends: 3	Another thing to add is the Prius will start the ICE immediately if you have the front defrost on. I'm pretty good at making sure it's off when I stop the car so I can engage EV mode on the next startup.

02-28-2006, 10:01 PM	#5
seasalsa Senior Member Join Date: Feb 2004 Location: Kent, WA Posts: 1,202 My Car: 2004 Prius Model: Package: #2 Thanks: 0 Thanked 1 Time in 1 Post Friends: 0	Since you failed to mention your location, I am assuming you live in a colder climate. If so, just wait till the weather warms up and your problem will solve itself.

02-28-2006, 10:06 PM	#6
galaxee resident lab rat Join Date: Mar 2005 Location: boilermaker territory Posts: 9,676 My Car: 2005 Prius Model: N/A Package: #5 Thanks: 0 Thanked 94 Times in 37 Posts Friends: 26	no adjustments like that are possible. the ECU program is a complete unit and cannot be tweaked to user preference. the car works to provide good fuel economy AND low emissions. the "low emissions" part is what's bugging you. but the car does what it has to do to warm up the engine and the cat in a timely fashion for emissions. nothing you can do about it. in short, they're not lying to you.

02-28-2006, 10:47 PM	#8
KTPhil Senior Member Join Date: Jan 2005 Posts: 1,313 My Car: Model: Package: Thanks: 0 Thanked 2 Times in 2 Posts Friends: 0	Search on "EV switch" and you'll find the many answers to your questions. It is one of the most popular topics here, along with running out of gas (sheesh). By the way, I've never seen an "adjustable computer." Well, I guess a slide rule qualifies...

03-01-2006, 08:17 AM	#10
tomdeimos Join Date: Feb 2004 Location: Lexington, MA Posts: 995 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	The car can definitely be adjusted. Mine is completely different since the SSC50P update. Before I had trouble staying electric. Now it is easy and I can do it even on some hills where it never happened before. Every computer update has tweaked things a bit differently from what I read hear. Only problem is we don't get to choose which update to get!