Welcome to Our Community

Wanting to join the rest of our members? Feel free to sign up today.

Sign Up

Power Loss

Discussion in 'Gen III 2010+ Prius Technical Discussion' started by jwads, Jan 23, 2012.

Social Buttons

  1. jwads

    jwads New Member

    Joined:
    Aug 3, 2009
    Messages:
    63
    Likes Received:
    0
    Location:
    Los Angeles CA
    Your Vehicle Year:
    2010 Prius
    Model:
    IV
    Was sitting in my car on my lunch break playing the radio and had my seat heater on, and all of a sudden my radio kinda went staticy and died and my car completely died. Had to power it back down then back up to get it running, battery didn't show very low, but when I went into start mode (non accessory) it immediatly started the ICE and charged.

    Wondering if this happened to anyone else?
  2. cwerdna

    cwerdna Senior Member

    Joined:
    Sep 4, 2005
    Messages:
    12,316
    Likes Received:
    1,925
    Location:
    SF Bay Area, CA
    Your Vehicle Year:
    2006 Prius
    Model:
    N/A
    What mode were you in? Were you in IG-ON or READY? If latter, where you in any "gear" other than Neutral?
  3. jwads

    jwads New Member

    Joined:
    Aug 3, 2009
    Messages:
    63
    Likes Received:
    0
    Location:
    Los Angeles CA
    Your Vehicle Year:
    2010 Prius
    Model:
    IV
    Im not sure. I was in what I call AUX mode, like where your radio and stuff works but the car won't drive b/c I hadn't pressed on the brake. I was still in park, wasn't driving in any gear
  4. cwerdna

    cwerdna Senior Member

    Joined:
    Sep 4, 2005
    Messages:
    12,316
    Likes Received:
    1,925
    Location:
    SF Bay Area, CA
    Your Vehicle Year:
    2006 Prius
    Model:
    N/A
    DO NOT run your Prius for too long in either ACC or especially ON (formerly known as IG-ON) otherwise you will drain the very small 12 volt very rapidly, which isn't good for it.

    I have a 2nd gen so I have no seat heaters (weren't available). ACC should be where the stereo works but you don't see any dash indicators. ON should be the above + turn all the warning lights initially and leave most of the dash indicators on. See pages 164-167 of your manual.

    If you want to sit there w/the stereo and esp. the seat heaters for a long period, you should be in READY mode (READY indicator on the left). Being in READY mode allows inverter to supply power to the 12 volt bus, charges the 12 volt and allows the ICE to fire up to maintain charge on the HV battery.
  5. ETC(SS)

    ETC(SS) Aspiring Hypocommuter.

    Joined:
    Oct 28, 2010
    Messages:
    2,708
    Likes Received:
    1,239
    Location:
    Redneck Riviera (Gulf South)
    Your Vehicle Year:
    2010 Prius
    Model:
    II
    Concur!
    You may want to start learning how to replace your 12V battery.
  6. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    Messages:
    18,046
    Likes Received:
    2,949
    Location:
    Northern Michigan
    Your Vehicle Year:
    2006 Prius


    Don't do that. That's the simple answer.

    Tom
  7. ken1784

    ken1784 SuperMID designer

    Joined:
    Dec 18, 2003
    Messages:
    2,895
    Likes Received:
    1,195
    Location:
    Yokohama, JAPAN
    Your Vehicle Year:
    2010 Prius
    Model:
    N/A
    Owners manual says...
    Code:
    [B]Auto power OFF function[/B]
    If the vehicle is left in ACCESSORY or ON mode (hybrid system is not operating)
    for more than an hour with the shift position in “Pâ€, the “POWERâ€
    switch will automatically turn OFF.
    Ken@Japan
    1 person likes this.
  8. kithmo

    kithmo Couch Potato

    Joined:
    Apr 25, 2010
    Messages:
    423
    Likes Received:
    54
    Location:
    South Yorkshire, UK
    Your Vehicle Year:
    2012 Prius+ MPV
    UK model turns ACC off after 1 hour to prevent flattening the 12v.
    just beat me to it Ken ;0)
  9. jwads

    jwads New Member

    Joined:
    Aug 3, 2009
    Messages:
    63
    Likes Received:
    0
    Location:
    Los Angeles CA
    Your Vehicle Year:
    2010 Prius
    Model:
    IV
    Good to know. I know I wasn't in that mode for an hour though, but still good to know. I was under the impression the Prius had a huge battery, so doing that wasn't a problem. Good to know!
  10. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    Messages:
    3,326
    Likes Received:
    1,437
    Location:
    Santa Fe, NM
    Your Vehicle Year:
    2005 Prius
    Model:
    N/A
    Charge that 12V asap. 2 amps for 10 hours.
    1 person likes this.
  11. jwads

    jwads New Member

    Joined:
    Aug 3, 2009
    Messages:
    63
    Likes Received:
    0
    Location:
    Los Angeles CA
    Your Vehicle Year:
    2010 Prius
    Model:
    IV
    Ya, ive been running it a lot since, and haven't kept it in AUX mode ever. How exactly does it flatten the battery? Why isn't it a normal charge recharge cycle?
  12. cwerdna

    cwerdna Senior Member

    Joined:
    Sep 4, 2005
    Messages:
    12,316
    Likes Received:
    1,925
    Location:
    SF Bay Area, CA
    Your Vehicle Year:
    2006 Prius
    Model:
    N/A


    The "huge battery" (the HV battery, in the metal box that runs the width of the vehicle) is not in use when you leave it in ACC or ON (aka IGN-ON) mode. It's running off the tiny 12 volt in the rear corner which is not being charged via the inverter while in those two modes.

    This is why you should be in READY mode if you want to run the radio, seat heaters or any accessories for any length of time.
  13. richard schumacher

    richard schumacher shortbus driver

    Joined:
    Mar 27, 2004
    Messages:
    7,652
    Likes Received:
    872
    Location:
    United States
    Your Vehicle Year:
    2004 Prius
    Model:
    N/A
    To sum up: leave it Ready, shifted to Park, and the parking brake set. Then you can listen to the radio until it runs out of gas, which will take something between two days and two weeks.
  14. jwads

    jwads New Member

    Joined:
    Aug 3, 2009
    Messages:
    63
    Likes Received:
    0
    Location:
    Los Angeles CA
    Your Vehicle Year:
    2010 Prius
    Model:
    IV
    Ya, Ill have to do that from now on, I always thought it used the huge car battery. Is there any way to get a charge on the little 12 volt in the back from any of the main indicators up front?
  15. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    Messages:
    3,326
    Likes Received:
    1,437
    Location:
    Santa Fe, NM
    Your Vehicle Year:
    2005 Prius
    Model:
    N/A
  16. qbee42

    qbee42 My other car is a boat

    Joined:
    Mar 2, 2006
    Messages:
    18,046
    Likes Received:
    2,949
    Location:
    Northern Michigan
    Your Vehicle Year:
    2006 Prius


    Your Prius must be Ready and not in N to allow the engine to charge the battery. If you sit in Park the engine will come on and charge when necessary, then turn back off.

    In Acc mode the small 12V battery is on its own; it doesn't get recharged by the big battery no matter how dire the level of charge.

    In Ig-on the 12V bus is being supplied by the big battery, but the engine cannot come on to recharge the big battery. All of the circuits are powered up in Ig-on, so it doesn't take a long time to run down the big battery.

    Tom
  17. lorraine

    lorraine New Member

    Joined:
    Apr 14, 2009
    Messages:
    39
    Likes Received:
    1
    Location:
    monroe, ny
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    My car losses power sometimes when I am driving it. I have to pull over and restart and then it is fine. Has anyone else had this problem?
  18. AtoyotA

    AtoyotA Junior Member

    Joined:
    Apr 15, 2010
    Messages:
    42
    Likes Received:
    9
    Location:
    Chicago area
    Your Vehicle Year:
    2012 Prius v wagon
    Model:
    Five


    Hmmm, good clear explanation of the difference. I was never quite sure which did what. Thanks!
  19. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    Messages:
    3,326
    Likes Received:
    1,437
    Location:
    Santa Fe, NM
    Your Vehicle Year:
    2005 Prius
    Model:
    N/A


    Can you give us more details? Do warning lights come on? Is the engine revving high, or is it completely off? Do you hear the hv battery fan running in the back?

    Power loss while driving is definitely not normal.
  20. lorraine

    lorraine New Member

    Joined:
    Apr 14, 2009
    Messages:
    39
    Likes Received:
    1
    Location:
    monroe, ny
    Your Vehicle Year:
    2010 Prius
    Model:
    III


    No warning lights come on. Not revving high, everything seems normal. I told my dealer about this and he said he did not have any other complaints.
    Car is fine otherwise. Can it be bad gas?
Similar Threads: Power Loss
Forum Title Date
Gen II Prius Care, Maintenance and Troubleshooting Power loss on start/stop Jun 9, 2014
Gen II Prius Care, Maintenance and Troubleshooting Loss of Power May 13, 2014
Gen II Prius Main Forum When turning I feel power loss, wondering if thats normal? Jan 30, 2014
Gen II Prius Care, Maintenance and Troubleshooting High RPM loss of power, fluttering noise from ICE Jan 20, 2014
Gen II Prius Main Forum A/C Compressor Replaced, now loss of power, bad smell ???? Sep 5, 2013