1. Attachments are working again! Check out this thread for more details and to report any other bugs.

DIY plug-in conversion Gen1 Prius

Discussion in 'Generation 1 Prius Discussion' started by der_Denis, Nov 5, 2014.

  1. Gen1newbie

    Gen1newbie Junior Member

    Joined:
    Oct 18, 2014
    41
    3
    27
    Location:
    Wildomar, California
    Vehicle:
    2002 Prius
    Model:
    N/A
    Denis,
    Here are the relays and fuses, I hope this helps.
    engine wiring.jpg engine wiring.jpg instrument wiring.jpg instrument wiring 001.jpg
     

    Attached Files:

  2. royfrontenac

    royfrontenac Member

    Joined:
    Feb 9, 2014
    247
    100
    0
    Location:
    Kingston Ontario Canada
    Vehicle:
    2001 Prius
    Model:
    N/A
    I have been trying to complete my service manual, I now have the volume for the 2003 troubleshooting volume and want to get the wiring diagram volume. I have the file in pdf form and can send it to you if you do not have it. It is too large for this site to send but If you email me at [email protected]. I will send it to you.
    I realize you cannot send your paper manual - thanks for answering my post.

    Roy from Canada
     
  3. Gen1newbie

    Gen1newbie Junior Member

    Joined:
    Oct 18, 2014
    41
    3
    27
    Location:
    Wildomar, California
    Vehicle:
    2002 Prius
    Model:
    N/A
    oops here is the page that should have been with the first one
    engine wiring 001.jpg
     
  4. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    989
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    I have been avoiding comment on this thread up until now but, I have decided to give my two cents. Take it for what its worth. I'm not trying to be a downer or naysayer but, this has been tried numerous times and here's my assessment.

    The Prius in general (Plug In excepted) is not a good candidate for "PHEV" conversion unless you use the "Enginer" (now called MD Tech, even that one has its issues and will only net you about 65 mpg max) type of conversion. Here's why:
    1) It is designed as a gasoline (primary) car with electric assist. It is for this reason that the electric motors do not have enough power to safely propel the car in many traffic situations. With electric mode only, the car is really underpowered and not safe or comfortable to drive on the streets
    2) The Prius has advanced, high-tech monitoring systems (called ECU's) that all work together to make this engineering marvel work. Adding more battery capacity requires modifying what one ECU sees which causes multiple problems with other ECU's.
    The old adage that "every time you fix a problem you have to solve another" has major application here. A typical scenario may go like this:
    Problem/Fix: The battery runs out or low in "EV/GolfCart" mode, I need a bigger battery (thousands of dollars)
    New problem: Adding a bigger battery requires spoofing or/reprogramming the Battery ECU
    Fix: Then I will reprogram/spoof the ECU so I can use the bigger battery (hundreds of dollars and lots of time)
    New problem: Now that I have this bigger battery and the ECU spoofed, the ICE still wants to come on when I accelerate normally
    Fix: I can use OutOfGas mode to stop the ICE from coming on (cheap)
    New problem: The stock electric motors/inverter setup are not strong enough to power the car in many situations and... if I want to use the ICE, I have to pull over, turn the car off and then back on to allow the ICE to be used (then you have the above problem of the ICE coming on too much)
    Fix: I need to install a larger electric motor (thousands of dollars)
    New problem: The inverter cannot power the new motor
    Fix: I need a new motor controller/inverter (thousands of dollars)
    New problem: I've spent so much money on converting my Prius that there is no return on investment and I can't sell it b/c no one wants a car that's had this many mods
    Fix: I need to take every mod off and return the car to its original state (thousands of dollars)

    It reminds me of a story I heard in grade school where a king had mice in his castle and wanted to get rid of them. So... he brought in cats then, he had too many cats so... he brought in dogs. This continued until he brought in elephants. Having too many elephants, the only thing he could think of to get rid of the elephants was mice. He brought back the mice, the elephants left and he lived happily ever after

    There are other numerous reasons why the Prius shouldn't be converted unless you're going to gut the HSD and add an electric drive system that can handle the requirements. The stock Prius electrical system is not designed to operate independent of the ICE. It needs the gas engine and the gas engine needs the electrical system. They have a symbiotic relationship, no amount of batteries can change that.
     
    royfrontenac likes this.
  5. Gen1newbie

    Gen1newbie Junior Member

    Joined:
    Oct 18, 2014
    41
    3
    27
    Location:
    Wildomar, California
    Vehicle:
    2002 Prius
    Model:
    N/A
    I know that the gen 1 is not the most desirable candidate for ev only mode, and that it has limitations. It must be the challenge that is the fun part. With that said, I think just controlling the brake line will keep the gas motor of, and let the car drive on battery only. I get in stop and go traffic that just is crazy trying to feather the gas pedal to keep the gas engine from starting. It would be nice to just have it off for those periods, I am just crawling on the roadway.
     
  6. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    989
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    Its not only the Gen I, all Gen's are undesirable candidates for EV only mode. They are all designed the same with very few differences.

    I'm not sure if I see how controlling the brake line will keep the gas motor off? Can you expound on that?

    Additionally, keeping the ICE off as you state will ultimately result in the ICE coming on to charge the battery (resulting in decreased mpg).
     
  7. Gen1newbie

    Gen1newbie Junior Member

    Joined:
    Oct 18, 2014
    41
    3
    27
    Location:
    Wildomar, California
    Vehicle:
    2002 Prius
    Model:
    N/A
    Well I think that when you put the brakes on the ICE turns off most of the time, and would turn itself back on when needed. As like when you are stopped at a traffic light. I'm wondering if the Gen 1 has an OOG mode? Maybe that is the way to go?
     
  8. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    989
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    The Gen I has an OOG mode but its def not the way to go. When OOG mode is tripped (usually by removing the fuel pump fuse), all kinds of codes will come up. Then you will be able to drive for a while on battery (albeit at a very slow acceleration and limited max speed of 52 mph). I highly discourage you from proceeding with this conversion. Unless you like wasting money and time, then I highly encourage you to proceed. :)
     
    royfrontenac likes this.
  9. Gen1newbie

    Gen1newbie Junior Member

    Joined:
    Oct 18, 2014
    41
    3
    27
    Location:
    Wildomar, California
    Vehicle:
    2002 Prius
    Model:
    N/A
    Well I don't want to pull the fuel pump fuse, to try this out. I just want to go in golf cart mode around 25mph. Would the engine try to start with the fuel pump fuse pulled? o_O
     
  10. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

    Joined:
    Jul 29, 2011
    3,159
    989
    0
    Location:
    Tucson, AZ
    Vehicle:
    2005 Prius
    Model:
    Four
    No, it will not. Once the ECU recognizes a lack of flow/pressure in the fuel line, it will not attempt to start the ICE.

    How far do you want to go in golf cart mode? And... How much are willing to pay for this capability?
     
  11. der_Denis

    der_Denis Junior Member

    Joined:
    Nov 5, 2014
    47
    22
    0
    Location:
    Germany
    Vehicle:
    2004 Prius
    Model:
    Base
    Long time no see.
    For the past 9 months i've been working on a conversion kit, sorry for not posting anything. I've been very busy lately.
    But i've made a good progress, as the alpha version is installed and works. I need to solve some small issues with the connections though.

    On the picture attached you see the kit itself. It's already installed into the car. I will send the picture later on.

    First results:

    Yes, the car is happy to run on electricity, as long as it detects enough "juice" ( more then 320 volt ).
    EV mode acceleration is good enough for the city driving as long as kit can supply up to 30 - 40 amp.
    Charging works fine. The total capacity of the kit is 17 Ah. The charger "pumps" 7.5 A into the pack, making the charging time for about 3 hours (220Volt AC socket).

    I will test the performance this weekend:
    in the city: range, EV acceleration, EV mode speed (ideally up to 72 km/h), HV battery temperatures
    on highways: fuel consumption (i expect double decrease over 100 km of distance)

    I'll post a video with the results.

    However, this morning i encountered a problem.
    I wanted to drive a car in EV mode, but the car ICE won't start.
    I checked the 12v battery, it's fine. Fuses - fine. Relays - all well.

    I have to note though, that when the car was off, i accidental turned on the kit into ready mode.
    First i need to explain "on the battery" level what it means "when the car was off". It means the prius HV battery (NiMH) is disconnected by a relay from the converter power lines. That's where my kit power lines are connected, simply in parallel to the NiMH battery.
    So here is the question. If the converter does not expect any voltage coming in it when the car is off (ignition key is not inserted), but i accidentally gave it 300 something volt (by switching my kit on), could this potentially damaged my converter and thus my ICE won't start?

    Or when the car is off, so is the converter for the sake of its protection?

    I hope i can resolve this before the weekend, so i can test the EV mode.

    Thanks in advance!
    Regards,
    Denis
     

    Attached Files:

  12. valde3

    valde3 Senior Member

    Joined:
    Jun 28, 2014
    2,002
    745
    0
    Location:
    Finland
    Vehicle:
    2004 Prius
    What do mean by “I wanted to drive a car in EV mode, but the car ICE won't start.”? If you want to drive in EV mode ICE shouldn’t start? How do you even get it to EV mode, stopping the fuel pump? Doesn’t that cause fault code?

    I would think that powering the high voltage line might cause high voltage contactor (relay) fault code. Do you have fault light? Did you read fault codes?
     
  13. der_Denis

    der_Denis Junior Member

    Joined:
    Nov 5, 2014
    47
    22
    0
    Location:
    Germany
    Vehicle:
    2004 Prius
    Model:
    Base
    For the Prius Classic 2001, to get the car into EV mode, you need to be gentle with the throttle.
    No, i don't take the fuel pump fuse out. I keep the car as standard as it is (no spoofing of the NIMH).

    This looks like what i have.
    I do, but i have a "christmas tree" light normally when the car runs with the kit on. This is because prius ECU detects extra circuit from my kit.
    Unfortunately i don't have any code reader, so i'm blind here.
     
  14. valde3

    valde3 Senior Member

    Joined:
    Jun 28, 2014
    2,002
    745
    0
    Location:
    Finland
    Vehicle:
    2004 Prius
    You can just try disconnecting 12V battery for some time to see if that clears the codes and gets it to work. But Mini-VCI is so cheap that you should just get one.
     
  15. der_Denis

    der_Denis Junior Member

    Joined:
    Nov 5, 2014
    47
    22
    0
    Location:
    Germany
    Vehicle:
    2004 Prius
    Model:
    Base
    That will be my next step. Hopefully this is only the relay fault that can be cleared by powering off the car from the 12v.
    Thanks!
     
  16. vaughnstark777

    Joined:
    May 4, 2012
    180
    33
    0
    Location:
    Roy, WA
    Vehicle:
    2001 Prius
    Model:
    I
    The Mini-VCI is less than $20 on ebay.
     
  17. der_Denis

    der_Denis Junior Member

    Joined:
    Nov 5, 2014
    47
    22
    0
    Location:
    Germany
    Vehicle:
    2004 Prius
    Model:
    Base
    Thanks. Disconnecting 12 volt for some time helped.
    I shell order mini-vci.

    Here is the update of the kit installed.
     

    Attached Files:

  18. valde3

    valde3 Senior Member

    Joined:
    Jun 28, 2014
    2,002
    745
    0
    Location:
    Finland
    Vehicle:
    2004 Prius
    Are you running the power wire to Power Inverter without fuse? How about those wires to HV-battery?
     
  19. der_Denis

    der_Denis Junior Member

    Joined:
    Nov 5, 2014
    47
    22
    0
    Location:
    Germany
    Vehicle:
    2004 Prius
    Model:
    Base
    Yeap, they are all fused.
     
  20. vaughnstark777

    Joined:
    May 4, 2012
    180
    33
    0
    Location:
    Roy, WA
    Vehicle:
    2001 Prius
    Model:
    I
    So when are you going to start selling them?