HV Battery Shows Charged but Kicks Off Intermittently

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by ElectricSlide00, May 17, 2022.

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  1. ElectricSlide00

    ElectricSlide00 New Member

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    2007 owner here. Beloved red triangle of death and assorted Christmas tree display popped up recently. Ultimately, I opened up the hybrid battery assembly and found one cell was coming in at 6.5V instead of the 7.8 every other cell was at.

    I replaced and cleaned everything up; the car was working beautifully again for about 70 miles or so. Then, although the hybrid battery display still showed a constant ~80% charge status (never fluctuated?), the red triangle reappeared and the hybrid system seemingly kicked off. On the display I could see no input/output from the battery, and vehicle power was greatly reduced again like it was when the error first appeared.

    Turning the vehicle off and back on again solves the problem temporarily, but after a mile or so the hybrid system kicks back off and the gas engine runs the show.

    Any advice or thoughts on why the hybrid system might use the battery, show it as full, but then cut it off?
     
    #1 ElectricSlide00, May 17, 2022
  2. Tombukt2

    Tombukt2 Senior Member

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    No not right off but I'd get it on tec stream and see if any HV codes I'm having the same issue on the 13 when I plug up it's original air conditioning compressor which is sitting in the car bolted to the side of the motor and cat was kept charged during my engine change but I plug up that compressor it tells me I'm draining the battery and some 1600 code about no communication with the compressor so I'm assuming that's the four or five pin connector on top of the compressor that switches the compressor on and off in between modes not just the high voltage connector the minute I plug up that high voltage connector drain starts happening and weirdness goes on it's telling me there's something wrong back in the battery tray area although inspection back there there's no leaks nothing running to ground no battery juice nothing matter of fact it was just replaced a few weeks ago the battery guy says it doesn't make any sense I can come back if I want but probably nothing to see or test was installed within three Delta supposedly
     
    #2 Tombukt2, May 17, 2022
  3. bisco

    bisco cookie crumbler

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    yeah, you're gonna need codes and sub codes.
     
    #3 bisco, May 17, 2022
  4. TMR-JWAP

    TMR-JWAP Senior Member

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    Codes would certainly be nice, but it's not out of the realm of possibility that we could go right back to what was worked on last.
    There could easily be a loose connection in the HV battery fasteners, a small crack in the wire frame #2 sensing tabs that are mounted with the busbars, corrosion on the ecu pins or wire frame #2 connector.

    Could even be something weird and unrelated to the HV battery like an inverter cooling water pump letting the inverter overheat.
    A good code reader will go a long ways to resolving this.
     
    #4 TMR-JWAP, May 17, 2022
    ElectricSlide00 likes this.
  5. mech1222

    mech1222 Junior Member

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    good version of techstream posted recently in 2nd gen forum, snowflake button to read sub codes, can get a bare mini vci for $30 some places and a win10 or 7 or xp computer and youll be using what the dealer uses...

    it would also show inverter temps and battery temps and block voltages, block voltages can show you voltage under motor load if its another bad cell or what block has the issue sometimes...
     
    #5 mech1222, May 21, 2022
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