hacking the computer?

Discussion in 'Generation 1 Prius Discussion' started by adric22, Jan 25, 2010.

  1. gene23

    gene23 New Member

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    Agree 100%. So far have experimented with large scale disruptions (disabling fuel pump, pulling EFI fuse, disabling IG2 relay) and some sensor mods, Master Cylinder press signal (which works to force regen) and fuel level sensor (which makes small effect in turn off/turn on of ICE but nothing even close to EV mode).

    Anyone know why the engine continues to run with the ignition coils and injectors disconnected from 12V battery supply?

    The consumption display goes straight to 100mpg, and all else seems to work OK (indications, power, regen, etc), but the ICE is still spinning. I even turned off the fuel pump and it kept going???

    And yes, its an experimental car and may not last long...
     
  2. adric22

    adric22 Ev and Hybrid Enthusiast

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    As I mentioned in another thread, something that should be tested is the idea of tricking the computer to believe the engine is overheated. My friend the toyota technician came up with this idea and thinks it will work, but I haven't gotten around to testing it. The idea is that if the prius believes the engine is overheated, it will shut it off and not start it again until the temperature cools down. So if we made a toggle switch on the dash that could short the sensor (or possible open, not sure which way it needs to go) then this might work. The only question nobody has an answer to at the moment is will the car stay in READY mode like it does when it is out of gas?

    I like the idea of charging the prius HV battery before a drive. At first, I didn't think this was possible since the relays are open while the car is off. But, it never occurred to me that if I turn the car on for a little while before I take a trip, the enginer system will charge the HV battery. With this in mind, it may be possible to drive back and forth to worth each day without ever turning the gas engine on. Starting with a full battery, combined with the 3000W continuous power from the enginer.
     
  3. linuxpenguin

    linuxpenguin Active Member

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    The Prius is different from most conventional cars in the sense that it electrically spins the gasoline engine block with MG1 before injecting fuel to extend the life of the engine. It's probably electrically spinning the gasoline engine while continuously trying to inject fuel to start it. It should sound a bit different than usual? I assume you're getting errors out the wazzoo? =)

    The question is, does it work properly after you re-enable the fuel line. Even if it does work properly, you still are clearing diagnostic and emissions related information and it's unclear what effect whatever you're doing would have on the Gen1 engine block.

    Andrew

     
  4. linuxpenguin

    linuxpenguin Active Member

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    My best guess (and I don't have a Gen1, but am familiar with Prius in general) is that the car will go into a fail-safe mode once the temperature goes too high. Generally fail-safe modes require the codes to be cleared and the vehicle restarted to be fully cleared.

    About the charging the HV battery up before using it with the Enginer system--really? Do you guys really do that--like for 20+ minutes, leaving the car running before using it?

    Andrew

     
  5. gene23

    gene23 New Member

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    Yes, that seems to be excatly what is happening, and the engine does sound different, like a very low power idle.

    I get 4 codes 1300, 1305, 1310 and 1315 - fuel inj failures

    And yes, as soon as I restore 12V thru IG2, all functions back to normal, i.e. on the fly.

    But it doesn't seem like the ideal solution, yet.
     
  6. gene23

    gene23 New Member

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    Yes, the DC-DC converter is set at about 1.4V per cell of the prius, so it tops off the battery but doesn't seem to overcharge. Under normal conditions, once warmed up, the engine will cycle on and off while in the ready mode. Just leave the converter on while charging. It helps to measure the DC output of the converter, but when it gets down to about .6A, I cut off the converter and let the all the charger output go to the LiFePo batteries. I usually do this when I recharge the Enginer and not necesarily before departing, but you could do it that way also.

    Gene
     
  7. linuxpenguin

    linuxpenguin Active Member

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    Yikes, sounds like a boo-boo on Toyota's part...I would have expected that to go into a fail-safe mode and prevent the gasoline engine from running again until the vehicle was power cycled (this is how the Gen2 reacts--and rightfully so, if the fuel injectors are failing you don't want the engine running). Interesting never-the-less. What sort of current draws are there with the car just sitting in that mode?

    Probably not the ideal solution since it would be running all the time and drain your battery much faster in addition to setting all those lovely codes (unless you want to enter your Prius as a Christmas tree :)). Plus it could be damaging the engine block or suctioning oil out of the engine.

    Regarding the letting your car charge up--I guess I was just surprised...I don't think I could handle doing that. I like being able to just unplug my car and drive off =).

    Andrew
     
  8. adric22

    adric22 Ev and Hybrid Enthusiast

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    When I tried this (by just pulling the relay out for OPEN-CIR) The engine would spin for a few seconds when first starting the car, then it would stop. After that it never tried to start the engine again until I cycled the key off and back on.

    I have not yet tried charging the main battery with the car sitting "on" I'm not sure.. will the relays close in the main battery just by turning the car on, or does it require actually starting the engine first?

     
  9. bwilson4web

    bwilson4web BMW i3 and Model 3

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    I've triggered a over heat condition once by using a too small resistor. The biggest thing is it triggers the fans to come on. I don't remember it turning the ICE off. The temperature sensor feeds to the engine ECU located behind and to the right of the glove box.

    BTW, I have a Graham scanner and it can clear codes but I don't remember if this enables engine start after faking a failure say by disabling the throttle plate drive motor.

    GOOD LUCK!
    Bob Wilson
     
  10. WU8Y

    WU8Y New Member

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    Ugh. That's too bad. You're exactly correct, that makes it much more difficult to deal with.
     
  11. adi

    adi New Member

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    hello. I have prius nhw10 year 1998 . my engine 1,5cc is gone. how make work only ev mode. I have battery lifepo4 320v 20ah. pelease help.
     
  12. joedirte

    joedirte Member

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    Just my two cents.. Relatively, one of the cheaper thing in prius to replace would be the 1.5L engine.

    Anyways, I'm guessing you would need to learn japanese and hope to find a website where someone did this in Japan.

    How do you have over 500lbs of LiFePo4 batteries??
     
  13. adi

    adi New Member

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    my battery have 320v 20ah 75kg
     
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