2004 Toyota Prius FAQ - Buttons and Gauges

How does the Power button work?
Help! The Power button doesn't work! (The car won't go to READY)
What happened to the Start button I saw in commercials?
When I park, do I have to push the "Park" button and turn off the headlights?
What's this I hear about the "Park" button having a sticker?
What is this "EV Button" I keep hearing about and is it an available option?



How does the Power button work?

The hybrid system will start and stop by pressing the "POWER" switch briefly with the brake pedal depressed.  Each time you press the "POWER" switch briefly without the brake pedal depressed, the hybrid system mode changes in the order of "OFF", "ACC", "IG-ON" and then back to "OFF".


Help! The Power button doesn't work! (The car won't go to READY)

Posted by Geoff Shepherd in Prius-2G:
Someone some time ago wrote about getting their 04 Prius "stuck" in IG-ON mode, but not READY mode. IG-ON is distinguished by the amber glow to the Power Button LED. If I recall, the situation "magically" resolved itself after a few minutes, or they pulled a fuse.

Here is what I did to reproduce the likely problem:

1. Make sure the parking break is set.

2. Press (Power) twice without holding the brake.
or
2. Hold the brake and press (Power), but release the brake at the same moment you release the (Power) button.

The car is now in IG-ON mode and the Power LED should be amber.

Hold the brake pedal and try shifting into D (or N).

[CAUTION] The car is now in IG-ON and in Neutral.

5. While still holding the brake pedal, try pressing the (Power) button.

Nothing happens! <insert optional panic and confusion>

The car appears to be "crashed." The only clues: no READY light, amber power LED, no green Park LED, gear indicator shows N, various warning lights are on. Opening the driver's door lights red <!> caution symbol and scolds you on the LCD (ironically, a message how to get out of this mode, if you read it at this point).

To get out of this mode:

6. Press [P], then (Power).
or
6. Release the brake pedal, then press Power.

Car should now be off and in Park.

Someone unfamiliar with the Prius could get into this mode, as could any of us who are just in a hurry to get going... you power up in a hurry, shift into Drive (or so you think), press the accelerator and nothing happens. Then you notice things look screwy, so you try to power down, but it won't. Had me the first time I did this.

It's odd that it won't let you Power down in this mode with the brake pedal pressed. You either must release it or select Park first. This is different than any other mode where you can normally just press (Power) to shut down. Maybe the Toyota engineers were originally going to enforce the rule of pressing Park before shutting down, but at the last minute they removed the code from all modes, except this one. Who knows. It seems to be an odd inconsistency. It should at least double-beep at you rather than just do nothing.


What happened to the Start button I saw in commercials?

There are Prius advertisements that show a "Start" button, but the button on the actual car reads "Power".  In reality, there never was a "Start" button. There used to be an "Engine/Start/Stop" button that morphed into a "Power" button.  Perhaps Toyota felt "Engine Start Stop" was too wordy, and not really appropriate given the hybrid nature of the car (gas engine and electric motor).


When I park, do I have to push the "Park" button and turn off the headlights?

No. To park, after you have stopped you can just push the "Power" button if you want, without pushing "Park" first.  Pushing "Power" will put the car into Park, and it will turn the car off.  When you open your door, the headlights will turn off.  So if you want, you can leave your headlights switch in the "on" position at all times.  This will mean your headlights are always on when driving, such as with Daytime Running Lights.  And you won’t have to remember to turn on the headlights when it gets dark.  (Note, however, that leaving the switch on drains a bit more battery power than leaving it off, so don't leave the  switch on if you will not be powering the car up for some time).


What's this I hear about the "Park" button having a sticker?

Early 04 Prius have a sticker on the Park button. The sticker only consists of the rounded-corner square (same as the symbol around the P on the dash display), not the "P". Many people have removed the sticker, as the Ports seem to not care whether it is installed squarely or not. People that have not removed it have noted that the square has noticable wear after 1000 or so miles (I'm assuming these people press Park every time they stop). Lately, some people are saying their cars have the square molded into the button, as the P is.


 

What is this "EV Button" I keep hearing about and is it an available option?

The "EV Button" is a feature that allows a user to "encourage" the car to stay in electric only "stealth" mode. This is currently available on Japanese and European models only. Using this mode precludes the use of the AC or heat.

The decision to not use the EV Button on the US version appears to be largely a Toyota decision.  It appears that Toyota never broached the issue with the EPA on how to test a vehicle with this capability. Toyota simply decided most Americans would not use it, or that it might confuse their marketing effort to show that you "just drive it" like any other car, so it was left off.

This feature could increase MPG, but may also decrease the life of the battery. The full extent of the EV button’s advantages and disadvantages are not yet fully available to the general public. People have speculated that the primary use for such a feature would be for doing things such as pulling the car out of the driveway.  Top Prius engineer Dave Hermance is on the record saying the EV button in Japan only works for a maximum of 1 kilometer. (TS - I find this hard to believe, as I have run EV only for longer than that in a US car without an EV button).

There are several FAQs on how to install either the factory button or an aftermarket button. One can be seen here, others are on the PriusChat site.






Last modified: Jan 7, 2004
Copyright 2003-4, Bill Robbins, Tom Stangl, Michelle Vadeboncoeur
VFAQ Prius, VFAQ.NET
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