Faulty battery connection?

Discussion in 'Gen 2 Prius Technical Discussion' started by amyz, Jun 7, 2010.

  1. amyz

    amyz New Member

    Joined:
    Jul 11, 2008
    12
    1
    0
    Location:
    Londonderry, NH
    Vehicle:
    2008 Prius
    I have an 08 Prius that for the 3rd time in 6 weeks has displayed the following lights: Caution light, VSC, and braking system lights as well has the hybrid warning light on the display screen. The first two times I was told that there was a loose connection to the battery and that the dealership fixed the problem (two different dealerships as the first time it happened I was out of town). Now this weekend it happened again - we had 4 people in the car and were going away for the weekend so we had luggage in the back as well. I'm bringing the car to the dealership this morning but figured I check quick to see if anyone else has had a similar issue. Thanks in advance!
     
  2. MandiRocker

    MandiRocker Junior Member

    Joined:
    Sep 5, 2009
    45
    6
    0
    Location:
    WV
    Vehicle:
    2005 Prius
    Model:
    N/A
    I have an '05 & have the those exact lights, mine is related to an intermittent short in the blower motor controller for the hybrid battery fan. I am taking it in this morning for service....will see how it goes.......Good luck with yours!!!
     
  3. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,963
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    Have them check the -ve battery cable where it connects to the chassis. There have been reports of corrosion at that bolt.
     
  4. MandiRocker

    MandiRocker Junior Member

    Joined:
    Sep 5, 2009
    45
    6
    0
    Location:
    WV
    Vehicle:
    2005 Prius
    Model:
    N/A
    Little bit of an update on my end....so far two ecu's are going to be ordered, HV & battery pack. Both are covered under the hybrid warranty. Will update again when I know more.
     
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,181
    6,285
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Does this mean that your car has three problems (so far), or was it decided that the fan motor controller is OK?

    Odometer reading?
     
  6. amyz

    amyz New Member

    Joined:
    Jul 11, 2008
    12
    1
    0
    Location:
    Londonderry, NH
    Vehicle:
    2008 Prius

    Thanks David, I will do that. I was sent home with a loaner - the dealership is calling Toyota as there are no service bulletins on this problem and they have no idea what is wrong! Off to call the dealership back and ask about the ve battery cable.
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,181
    6,285
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    The dealership will not know what a "ve" cable is, but they will know what a "negative" battery cable is.

    Surely your car has logged some DTC (diagnostic trouble codes)? I suggest you ask what they are, and post.
     
    1 person likes this.
  8. amyz

    amyz New Member

    Joined:
    Jul 11, 2008
    12
    1
    0
    Location:
    Londonderry, NH
    Vehicle:
    2008 Prius


    Drat, and I was trying to sound so smart!!

    I will ask about the DTC when I speak to the service guy in the morning and then post the response...Thanks Patrick.
     
  9. amyz

    amyz New Member

    Joined:
    Jul 11, 2008
    12
    1
    0
    Location:
    Londonderry, NH
    Vehicle:
    2008 Prius
    Have my car back, according to the dealership: "found code P0A0D, high voltage service connector" and further it says: "Contacted TAS, per instructions re-checked service interlock circuit, found intermittent open in service grip detection circuit inside battery housing. Found 2-pin connector inside housing loosely connected causing intermittent open. Reconnected and cleared codes"

    So I'm happy that they found "something" I'm just hoping that this "something" is what was causing the problem!
     
    1 person likes this.
  10. Rokeby

    Rokeby Member

    Joined:
    Jan 21, 2008
    3,033
    707
    75
    Location:
    Ballamer, Merlin
    Vehicle:
    2008 Prius
    Congratulations :cheer2:

    I'm hoping that the troubleshooting gurus will translate/rephrase/decode
    this so that I/we can understand what the heck it means:

    :confused:
     
  11. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,181
    6,285
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    The traction battery has an orange safety interlock plug located on the left side of the battery case. The interlock plug contains a switch that tells the battery ECU if the interlock plug is not properly installed. Apparently the wiring to that switch was intermittent.

    I'm concerned because the original post says a similar problem (loose connection to the battery) was already discovered and worked on by two other dealerships. Amy, does the repair invoice show any replaced parts?
     
    1 person likes this.
  12. andyprius

    andyprius Senior Member

    Joined:
    Feb 21, 2005
    2,212
    176
    0
    Location:
    Sacramento, California.
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    You are speaking of the 12 Volt system?
     
  13. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,963
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    Yes, the 12V battery in the right rear of the hatch area.
     
  14. amyz

    amyz New Member

    Joined:
    Jul 11, 2008
    12
    1
    0
    Location:
    Londonderry, NH
    Vehicle:
    2008 Prius

    Patrick, the invoice show no replaced parts. Pulled the paper work on the previous service and found that it says "found that service grip connector on the side of the hybrid battery wasn't latched correctly causing loose connections" - again no parts. No diagnostic codes are listed on the paperwork.

    Unfortunately the paperwork from the first service is not where it should be...will require a little more looking.
     
  15. andyprius

    andyprius Senior Member

    Joined:
    Feb 21, 2005
    2,212
    176
    0
    Location:
    Sacramento, California.
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    OK. So far it looks like a fault in the HV interlock switch, OR further down the line. Possibly previously the switch was played with by somebody not understanding how it works. I recommend that everybody should disconnect and remove this switch and study it's operation. Make sure car is OFF. Will not hurt anything. In a emergency you will be able to show the firemen, police, etc where the disconnect is.
     
    1 person likes this.
  16. amyz

    amyz New Member

    Joined:
    Jul 11, 2008
    12
    1
    0
    Location:
    Londonderry, NH
    Vehicle:
    2008 Prius


    Thanks for the info/advise - think I'll have my husband do this with me.
     
  17. efusco

    efusco Moderator Emeritus
    Staff Member

    Joined:
    Nov 26, 2003
    19,890
    1,167
    9
    Location:
    Nixa, MO
    Vehicle:
    2004 Prius
    Model:
    N/A
    Amy,
    All due respect to Andy (and I really do respect him and his knowledge), in this particular case I would suggest NOT touching the battery interlock. The risk/danger to you/your hubby is minimal, but we are talking about high voltage and it is normally recommended that when dealing with that part of the car one use proper precautions, thick rubber gloves, etc.

    But, maybe more importantly, I think it is better if you can honestly say you did not touch anything around that part of the car. It is highly unusual to have the problem you describe, and even more unusual that it has happened twice. I am worried that the interlock might be broken and has a loose pin or something. If you touch it and then can't get it reconnected then the dealership might be able to blame you for the problem and then not cover it under warranty.

    I think I would leave it alone...if the problem occurs again I would insist that they explain why this has happened 3 times and what they are going to do to make sure it doesn't happen a 4th time...maybe suggesting that the interlock needs to be replaced b/c it appears to be faulty. And if it never happens again then great...most of us go through our entire Prius ownership experience without ever looking at that interlock so much as touching or opening it.
     
  18. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,181
    6,285
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    I agree with Evan. The interlock switch requires the handle to be pivoted, then slid to lock in place. The sliding part of the procedure is often overlooked which results in the vehicle not working. If the car is working, no need to mess with the interlock switch.
     
    1 person likes this.
  19. andyprius

    andyprius Senior Member

    Joined:
    Feb 21, 2005
    2,212
    176
    0
    Location:
    Sacramento, California.
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Hi Pat and Dr! Thankyou for your kind words. I too thought only of the danger involved with playing, investigating, actuating the " High Voltage " switch. It's kind of like mushrooms, if you know nothing about the subject, don't experiment. I totally agree with Hobitt that the danger is exagerated.The warnings on the case are for the neophyte. The general public should be cautious. Actually I don't believe that there is a danger even if one was to touch the two copper connections inside the battery and grounded with the other hand. ( even tho I proved this with my DVM I still would not try it ) I already tried to measure this EMF and of course the chassis ground does not apply to the HV system, thus no reading on my meter. Toyota has done an excellent job of isolating the common ( or negative ) And I presume it is in or around the Motor/Generator units. If there was truly a danger there, no firemen &/or policemen would be instructed as to it's use. It would be dangerous right? However you are right in mentioning the difficulty of reinsertion, it's a little tricky, but doable. Next time I remove the HV switch I'll mark it with a magic marker so the alighnment is correct, initially. Otherwise it takes several attempts. I have picked and eaten several types of mushrooms, because I have studied the subject. Same thing with electronics. I always keep one hand in my pocket. ( no smiling allowed! )
     
  20. andyprius

    andyprius Senior Member

    Joined:
    Feb 21, 2005
    2,212
    176
    0
    Location:
    Sacramento, California.
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    After removal, one can operate that interlock and plainly see how it works, possibly the mechanic did not remove it, therefore did not inspect its operation. So, it could vibrate out again.
     
Loading...