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***FIXED*** Just bought my 2004 Prius, some lights on... (Red Triangle, VSC, (!) and Red car with !

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Vasilis, Aug 31, 2015.

  1. ChapmanF

    ChapmanF Senior Member

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    While you posted a drawing that shows basically where the relevant components are, I hope that you also found the wiring diagram and the steps for diagnosing the fan control.

    Keep in mind that there are not only relays involved, but a pulse-width motor controller, and a simple multimeter may be limited in what it can show you about that (probably just an average voltage, which might tell you enough to be useful; even better if it has a scope function). If I'm not mistaken, there is a Battery ECU (not the same as the HV ECU) that provides the driving signal to the motor controller ... unless that changed after Gen 1.

    -Chap
     
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  2. Vasilis

    Vasilis Junior Member

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    Well we have tried to test the relay but we did not have a 12V source, no cable to connect to the battery.
    I will get some cables and test the relay tomorrow.
    What we did though today we have waited until the lights came on. So the car was saying ot the fan to come on. And we put in the multimeter to see if we are getting power to the relay plug
    WP_20150903_22_11_25_Pro.jpg We found out that the bottom two pins are giving out 13.6V or around that value.
    WP_20150903_22_11_39_Pro.jpg So the gold/copper contacts are the ones that take the electricity for the car.

    WP_20150903_22_11_25_Pro.jpg If I put in a cable to short/connect the two top ones together will that put the fan to work on permanently? Has anyone done this? If this succeeds then this will prove the problem is the relay. Am I right thinking that?


    By the way we did come to the conclusion the fan is the whole cause of the problem. The lights only come on when the fan is meant to come on. There does not seem to be any other problem other than the fan not working. This seems to be the sole cause. :)
     
    #42 Vasilis, Sep 3, 2015
    Last edited: Sep 3, 2015
  3. ChapmanF

    ChapmanF Senior Member

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    Vasilis,

    I cannot strongly enough recommend that you follow the troubleshooting procedure in the manual. There is more involved in this circuit than you think.

    Your proposal to short "the two top ones" together does not look promising to me, at least not if you uploaded that photo right-way-up. By the way, the wiring diagram will have a picture of that connector and show wire colors and contact numbers, which will give a way to discuss troubleshooting steps much less vulnerable to miscommunication or misunderstanding. Your plan to test the relay on a bench tomorrow does seem sound to me. I would not do any shorting of any pins at the car unless your bench test of the relay indicates a problem. (Or even then, really, because if the relay tests bad then you just put a good one in. If the problem still exists after that, then more troubleshooting is called for, and the manual is still the best source for how to approach it.)

    If you are impatient to be doing something useful between now and tomorrow when you can get cables, it would be useful to study the manual and wiring diagram. :)

    -Chap
     
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  4. Vasilis

    Vasilis Junior Member

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    Just found some diagrams.
    By the way the pictures on my previous post where it shows the relay plug and relay, it is the right way up. Not upside down.

    dash wiring.JPG electrical wiring routing.JPG HV battery text.JPG hv system and battery diagram.JPG position of parts in body.JPG


    I am going to test the relay on the bench tomorrow morning. I know it is meant to be 0.5ohm and below to be a good one. So let's see :)
    I was only trying to see if anyone has tested the fan coming on from the relay plug. To test the circuit that way.
     
    #44 Vasilis, Sep 3, 2015
    Last edited: Sep 3, 2015
  5. ChapmanF

    ChapmanF Senior Member

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    Well, three of the five images you just posted do come directly from the wiring diagram manual (a ~ 200 page book), but unless you found them somewhere that has the rest of the pages, so you can find the ones from section H that explain your circuit, and the ones from section K that identify the terminal positions, and the troubleshooting steps from the service manual (a separate book), you may find that there is absolutely no easier way to get the information you need to make this repair than to go to toyota techinfo where all of it is, and save yourself all of the hunting around for random fragmentary portions on the internet, which has consumed a good deal of your time already, and the thing about time is you never get it back.

    Thanks for the confirmation, that's what I was afraid of. If the "two top ones" in that photo are the ones you were thinking of shorting, you would have a strong chance of burning out the relay drive circuit inside your battery ECU. On top of adding the cost of a battery ECU to your ultimate repair bill (unless the ECU happens to be what you need anyway), that would further complicate your troubleshooting, because finding one problem is a lot simpler than causing a second problem and then having to find two interdependent ones.

    Are you beginning to see why I sound like a broken record that you should make the effort to get the information you need so you can effectively fix your car?

    -Chap
     
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  6. Vasilis

    Vasilis Junior Member

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    I do see what you mean. I did not think of the Battery ECU damage if short circuit..
    The wiring diagram has everything and also the service manual there.
    But as you understand as a novice it is easy to get lost :)
    I will look more into depth tomorrow as it is now 1:15am here

    This is where the service manual and the wiring manual is located
    Service Manual
     
  7. ChapmanF

    ChapmanF Senior Member

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    Ok, that's handy. (Pirated, but handy.) Your fan control circuit appears in the wiring manual on pages 103 and 104, and the connector B14 that you photographed above is shown on page 379. From there it looks like you were proposing to short terminals 1 and 2, and flipping back to pages 103-4 you can see why it is probably good that you didn't.

    There are some troubleshooting steps for you in the "21 - Hybrid Control" section, on pages 21-36 to 21-39. Probably a good place to start.

    Even more diagnostic information would be in the "05 -Diagnostic" folder under HYBRID BATTERY SYSTEM but whoever pirated this stuff just dumped a boatload of PDF files in there with nonobvious names and no map ... one could probably open them all and find out which sections are which, but to me I think it would be worth $15 to not do that.

    Some things you should find quite helpful to learn your way around are sections B and C in the wiring diagram (depending on your background, C might be largely review for you, but still can be useful) and of course section "01 - Introduction" of the main manual.

    One really valuable manual that seems not to have been included in that upload is what is called the New Car Features Manual. It is the best source anywhere for just obtaining your initial basic understanding of what goes on in your car.

    -Chap
     
  8. ChapmanF

    ChapmanF Senior Member

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    If it is puzzling how the blower motor control works, you can scroll down to hobbit's explanation here (near the end).

    -Chap


    ... it tickles me somehow that the spelling "Busber" for bus bar, which I had noticed before in my Gen 1 wiring manual, still wasn't fixed for Gen 2. Anybody know if it's fixed in Gen 3? :)
     
  9. Vasilis

    Vasilis Junior Member

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    Well this explains why the active test of the cooling fan keeps coming up with an error. It wants no DTC code to be present. So I cannot test it when the car has been used for the day. I will try and do it this morning.
    active test.JPG
     
  10. Vasilis

    Vasilis Junior Member

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    wow :) the fan is now fixed!!!! woohooo :)
    the wiring loom was broken, water must have gone in the past on the opposite side of the car, between the wheelarch and the light (same side as the battery ECU.)
    The brown cable was totally broken. I could not find a little blade to repair the plug. So I bought another plug and rewired all the cables in the new one.
    So I have ran the test with the miniVCI again and passed with flying colours, all the speeds and no faults what so ever :)

    Now I need to take the car out for a test drive tomorrow. But I am certain everything will be fine.
    Guys thank you so much for your advice and help!!
    This whole fix cost me only £4,50! :) :) IMG_20150904_192424470.jpg I just need to find a way to secure the new plug so it does not move about.

    Here are the pictures of the damage and before the fix.

    IMG_20150904_170832835.jpg
    IMG_20150904_170846616_HDR.jpg
    IMG_20150904_170854242_HDR.jpg
     
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  11. geekwithoutacause

    geekwithoutacause Junior Member

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    wow, good thing you found it !
    While you are int here, did you clean the fan ? It gets clogged over time.
     
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  12. bisco

    bisco cookie crumbler

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    well done vasi!(y)
     
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  13. ChapmanF

    ChapmanF Senior Member

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    Satisfying to nail the problem, isn't it? (y)

    -Chap
     
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  14. Vasilis

    Vasilis Junior Member

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    Thanks guys.
    Yeah for sure it is satisfying fixing and problems and pin pointing the cause.
    Now at least I can spend money and fix all the exterior cosmetics with my Prius :)

    Yes the fan was clean enough but I am cleaning it even more to come to as good as new condition. I am not planning to remove it again soon so better be the cleanest it can be lol.
     
  15. ChapmanF

    ChapmanF Senior Member

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    So that turned out to be connector BM1 shown on page 63 (and 104), right?

    Just to leave a few breadcrumbs for the next person. :)

    -Chap
     
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  16. Vasilis

    Vasilis Junior Member

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    Yeap Chap spot on. This was the socket that needed replacing. BM1 :)
     
  17. Vasilis

    Vasilis Junior Member

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    I can with confidence say that this thread is now complete :) I just got back from a 230 miles trip, and the car worked flawlesly.
    I even got about 5-6 imperial MPG better than before. So the Hybrid system is sorted.

    Who knows how much would it have cost had I taken it to a garage or Toyota them selves ....

    I will now do some preventative maintenance, such like clean the MAF sensor, clean the throttle body etc. Just simple things in the engine bay. Make sure that the car is in good order.
     
  18. 2009Prius

    2009Prius A Wimpy DIYer

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    Nice!
    Change the transaxle fluid if it's never been done before.
     
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  19. Vasilis

    Vasilis Junior Member

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    I shall do :) for sure :)
     
  20. edthefox5

    edthefox5 Senior Member

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    Typically that area will only get wet if the cabin has a leak.

    That area has many reports of body cracks that allow water into that area from the top of the rear hatch hinge area then it drips down and collects in the 12 volt battery well and below the spare tire. Pull the spare tire out and check for water pooled there and then with a flashlight check in the battery well for standing water under the 12 volt battery.

    I had a leak behind my rear brake light assy and chased it for a while and couldn't find it so in the meantime I removed the drain plug under the spare tire and the there's also a drain plug in the bottom of the 12 volt well. If you park outside I might not do that as the Prius is a mouse magnet. I garage mine.

    The main reports of body crack leaks are happening in the hatch valley along the top ridge in the corner right by where the hinges mount to the body. Think where the rear quarter panel is welded to the roof. In the valley. Cracks will run along the corner valley area and up the valley on the roof above the side windows. The welds crack. That valley meeting area is covered by the black plastic strip that runs from the back to the front on each side of the roof. You can just pop that plastic strip off for inspection. It just pops back on.

    If I were you I would go to toyota.com/owners and join and put your vin in there and all the service records the car has ever seen at an authorized Toyota dealer will be logged there. I use that site to log all my diy also.

    I'm not sure if that site works in the UK. Curious to know. I know it doesn't have the records system in Hawaii. But lots of times the last entry will be the main reason the previous owners traded the car in. Many a poster here after buying an auction car found out the last visit it saw at a dealer the dealer determined the Hybrid battery was bad or the car had a knocking motor so the car was traded in on the spot.

    Off to auction it goes.....you know the rest.
     
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