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Need to know where the C/OPN relay is, with image if possible

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by TheSnowSnake, May 22, 2015.

  1. TheSnowSnake

    TheSnowSnake Junior Member

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    Still tiring to get the ICE to run and what to trace the voltage to this relay. Some users call it fuel relay other call it different names. I have the electrical manual but it doesn't show where the little devil lives. :rolleyes:
    It is refereed to in the manual as the C/OPN relay and is connected to the fuel pump.

    Thanks again...
     
  2. ChapmanF

    ChapmanF Senior Member

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    It definitely should, unless Toyota drastically worsened their manuals after my Gen 1. Make sure you check in one of the sections toward the front of the book showing 'fuse and relay locations' or 'wire harness routing'. In one of those diagrams every connector that's shown will be pointed to by an arrow and a letter-number code (like F9 etc.), which are the same codes used in the section toward the back that shows you the shape, color, and pinout of every (FRU) connector in the car (and the table after that, where their part numbers are shown).

    Toyota's electrical manuals are really good....

    -Chap
     
  3. valde3

    valde3 Senior Member

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    C/OPN relay is part of the integrated relay in the left (driver side for US) fuse box. Wiring manual shows it and what connections it is connected to. If that relay was faulty engine would crank but not start (Prius cranking sound like running).

    What does your Prius do when trying to start? Ready light? Cranking? Starting? Fault codes?
     
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  4. TheSnowSnake

    TheSnowSnake Junior Member

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    Oh ya I can find it in wiring diagram But where is it physically. It refers to it about 6 places .Left side under hood?
     
  5. TheSnowSnake

    TheSnowSnake Junior Member

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    I have many refers in the manual but no physical location divers side under hood?
     
  6. TheSnowSnake

    TheSnowSnake Junior Member

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    I'm unable to do anything, beyond key on and ready is not always lit, the big battery is real low but 12 is full.
    I will post codes as soon as my reader arrives. Also ordering a grid charger for main.
     
  7. ChapmanF

    ChapmanF Senior Member

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    I'm confused. In my wiring manual (this won't directly help you because we have different generations), there is a section F called "relay locations". The very first page of section F (happens to be page 20 in my manual) shows a diagram of the underhood area with the relay boxes (my generation has three) drawn in, exactly where they are and what they look like. Mine are labeled "engine room J/B", "engine room R/B no. 2", and "engine room R/B no. 3". Yours will be whatever they are in the Gen 2.

    If I flip about 6 pages further in, still in section F, there's a two-page spread showing "engine room J/B" in all its glory, top and bottom views. At the top of the page it says "Engine Compartment Left (See Page 20)" (which was the page showing exactly where it was in the engine compartment, remember?). The position and shape of each fuse and relay socket is drawn in, and they're all labeled, and one of them has the label "CIR OPN Relay".

    Have you found the section like this one in your own wiring manual?

    -Chap
     
  8. ChapmanF

    ChapmanF Senior Member

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    Also, if I look in section H, which is the one with all the detailed circuit diagrams, the "engine control" block of diagrams is shown on pages 68–76 (again, these'll be my page numbers, not yours). That's probably where I would have started my search, since that's where I'd see the diagram schematically connecting the relay to the ECM and the fuel pump.
    erjba.png
    See how it shows the relay wired to connectors coded 1A and 1F in little ovals (terminals 3 and 10 in connector 1A, 1 and 13 of connector 1F)?

    Now just flip to the last page of that "engine control" diagram block (76, in my book):
    jbloca.png
    See how the table title shows the oval shape used for the connector labels, and for both codes 1A and 1F it says see page 27? That was the page I mentioned that in my book has the two-page spread of the junction box labeling the exact position and shape of the relay socket ... and the top of that page says "see page 20" which is the one with the diagram of the engine compartment showing exactly where the whole box is.

    As I said, this stuff won't be directly right for you because you need to look in your own manual for your year, but I hope this might help you find your way around it.

    -Chap
     
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  9. valde3

    valde3 Senior Member

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    Yes under hood fuse box one the left side. My wiring manual (which is the correct one for yours) shows the location on page 22. And then shows the inner circuit in the page 24 and 25.

    But why are you interested in this now? Prius might not turn the C/OPN relay (fuel pump) on until the engine is cranking.

    First get the hv-battery charged and fault codes read. And stop putting it to ready until the hv-battery is charged! You don’t want to break the hv-battery.

    Probably only thing that you can do with that relay is to connect the pin 8 of connector 3G to power to test that your fuel pump (and wiring going to it) works.
     
    #9 valde3, May 23, 2015
    Last edited: May 23, 2015
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  10. TheSnowSnake

    TheSnowSnake Junior Member

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    Well I have had it to the point where I could drive it short distances. But need to get the ICE to run. Now my main is low enough that all operations are on hold until I get the codes and start some repairs. I was just wondering if the fuel relay was operating, as I don't think it is getting fuel. When it did drive it was on HV only. So all is on hold waiting for the scanner..........
    Thanks a ton guys
     
  11. Mendel Leisk

    Mendel Leisk Senior Member

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    Yeah, driving on just the hybrid battery is not progress, could be killing it.
     
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  12. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The circuit opening relay is one of the four relays that comprise the integration relay assembly. The integration relay is in the main relay/fuse box next to the inverter. I believe this is marked as "C", and it is a long and narrow black rectangular part. There is a similar-looking part labeled "B", but the B relay assembly also contains four fuses. The B and C relay assemblies are located in the upper right corner of the relay/fuse box (closest to the driver's fender).
     
    #12 Patrick Wong, May 23, 2015
    Last edited: May 24, 2015
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  13. TheSnowSnake

    TheSnowSnake Junior Member

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    Thanks I check that out. Thank Patrick
     
  14. TheSnowSnake

    TheSnowSnake Junior Member

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    Ok the grid charger is on right now charging up the HV battery. I want to reset all the error codes how do I do this??
     
  15. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Did you receive Mini VCI yet?
    It would be better for you to retrieve the existing DTC before you erase them. Most DTC will be lost simply by disconnecting the 12V battery.
     
  16. TheSnowSnake

    TheSnowSnake Junior Member

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    I have them and nothing really scary except the HV battery so Im charging now. And no the 12 volt removal did not reset the service light and some of the error codes. So how do I wipe them out for a fresh start.
     
  17. Patrick Wong

    Patrick Wong DIY Enthusiast

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    What are the DTC?

    What "service light" are you referring to?

    Other than DTC logged by the skid control ECU and SRS ECU, all other DTC will be erased simply by disconnecting the 12V battery. So if those DTC persist, that is because the problem causing those codes still exists.
     
  18. TheSnowSnake

    TheSnowSnake Junior Member

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    Yes read the codes. and most are in the history file

    hv battery U0100 Pending and history

    ABS/VSC/TRAC C1259 and C1310 Current
    Air conditioner B1411, b1412,B1421 Current

    Gateway B1271 History
     
  19. TheSnowSnake

    TheSnowSnake Junior Member

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    Maintenance required Patrick
     
  20. TheSnowSnake

    TheSnowSnake Junior Member

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    Also DTC C1259 HV system Regenerative malfunction
    and
    C1310 HV system manfunction