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2001 Prius - P3000/123 & P3125/287

Discussion in 'Generation 1 Prius Discussion' started by Prius4645686, Jun 27, 2012.

?

What should I replace first?

Poll closed Aug 15, 2012.

  1. 12V Aux. Battery

    0 vote(s)
    0.0%

  2. Battery ECU

    0 vote(s)
    0.0%

  3. Inverter

    0 vote(s)
    0.0%
Multiple votes are allowed.
  1. Prius4645686

    Prius4645686 New Member

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    Vehicle:
    2001 Prius
    Model:
    One
    Car stalled and ran on battery only. Set code P3125, and depleted aux battery.
    So, I replaced the inverter and recharged aux battery.

    Drove it 20-30 miles test driving it, when the MIL came on.
    Drove home and found 2 codes set, 1st was set while driving, 2nd was set after parking.

    P3000/123 - MPH=22 MG2.RPM=1280 SOC=65% Position=D
    P3125/287 - MPH=1 SOC=60% Position=P

    Anyone know of any TSB on this issue?

    What should I replace first? Aux Battery, Battery ECU or Inverter
     
    #1 Prius4645686, Jun 27, 2012
  2. Prius4645686

    Prius4645686 New Member

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    Vehicle:
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    Model:
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    UPDATED INFO:
    Seemingly, the Aux battery charge was fine when the first code triggered while driving.
    You'll notice the aux battery hasn't been charging when the inverter code comes up.
    Also, apparently, the inverter code was triggered after I restarted it to scan it, as evidenced by the Warm up and Idling Requests.

    P3000/123
    ----------------------------------------
    Water Temp Meter 196 F
    Engine RPM 1184 rpm
    Vehicle Speed 22 MPH
    Intake Air 113 F
    Detail Information 1 0
    Detail Information 2 123
    Detail Information 3 0
    Detail Information 4 0
    Detail Information 5 0
    123-Information 2 123
    123-Generator(MG1) Rev 768 rpm
    123-Motor(MG2) Revolution 1280 rpm
    123-Generator(MG1) Torq -24 Nm
    123-Motor(MG2) Torq 8 Nm
    123-Request Power 9120 W
    123-Engine Speed 1152 rpm
    123-Master Cylinder Torq 0 Nm
    123-SOC 65.85 %
    123-Drive Situation ID 4
    123-Inverter Temp (MG1) 149 F
    123-Inverter Temp (MG2) 129 F
    123-Motor Temp (MG1) 162 F
    123-Motor Temp (MG2) 273 F
    123-Power Resource VM 304 V
    123-Power Resource IB 0 A
    123-Shift Sensor 1 D
    123-Accel Sensor Main 34.49 %
    123-Engine Stop Request No
    123-Engine Idling Request No
    123-Engine Fuel Cut No
    123-Main Battery Charg Req No
    123-HCAC OBD Request No
    123-Engine Warming Up Req No
    123-Stop SW No
    123-Cruise Control No
    123-Auxiliary Battery Voltage 13.72 V
    123-Exclusive Information 1 -127
    123-Exclusive Information 2 -127
    123-Exclusive Information 3 -127
    123-Exclusive Information 4 -127
    123-Exclusive Information 5 -127
    123-Exclusive Information 6 -127
    123-Loading Condition MG2
    123-Driving Pattern 1 Lo Spd
    123-Driving Pattern 2 Mid Spd
    123-Driving Pattern 3 Lo Spd
    123-IG OFF in Driving No
    123-SG B in Reduction No
    123-SG N in Reduct or Park No
    123-Acceleration & Brake No
    123-Soak Time 0 min
    123-Occurrence Order 1


    P3125/287
    ----------------------------------------
    Water Temp Meter 142 F
    Engine RPM 0 rpm
    Vehicle Speed 1 MPH
    Intake Air 131 F
    Detail Information 1 287
    Detail Information 2 0
    Detail Information 3 0
    Detail Information 4 0
    Detail Information 5 0
    287-Information 1 287
    287-Generator(MG1) Rev 1152 rpm
    287-Motor(MG2) Revolution -128 rpm
    287-Generator(MG1) Torq 24 Nm
    287-Motor(MG2) Torq 40 Nm
    287-Request Power 0 W
    287-Engine Speed 0 rpm
    287-Master Cylinder Ctrl Trq 0 Nm
    287-SOC 63.50 %
    287-Drive Situation ID 2
    287-Inverter Temp (MG1) 142 F
    287-Inverter Temp (MG2) 133 F
    287-Motor Temp (MG1) 147 F
    287-Motor Temp (MG2) 151 F
    287-Power Resource VM 292 V
    287-Power Resource IB 16 A
    287-Shift Sensor 1 P
    287-Accel Sensor Main 0.00 %
    287-Engine Stop Request No
    287-Engine Idling Request Yes
    287-Engine Fuel Cut Yes
    287-Main Battery Charg Req No
    287-HCAC OBD Request No
    287-Engine Warming Up Req Yes
    287-Stop SW No
    287-Cruise Control No
    287-Auxiliary Battery Voltage 11.52 V
    287-Exclusive Information 1 64
    287-Exclusive Information 2 9
    287-Exclusive Information 3 -3
    287-Exclusive Information 4 7
    287-Exclusive Information 5 36
    287-Exclusive Information 6 8
    287-Loading Condition MG1
    287-Driving Pattern 1 Lo Spd
    287-Driving Pattern 2 Lo Spd
    287-Driving Pattern 3 Lo Spd
    287-IG OFF in Driving No
    287-SG B in Reduction No
    287-SG N in Reduct or Park No
    287-Acceleration & Brake No
    287-Soak Time 0 min
    287-Occurrence Order 2


    Any and all help is greatly appreciated.
     
    #2 Prius4645686, Jun 27, 2012
  3. joedirte

    joedirte Member

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    Vehicle:
    2003 Prius
    Model:
    I
    Any time you are in ON especially if the engine is running, the 12V battery should be seeing 13.5 to 13.9V.

    "287-Auxiliary Battery Voltage 11.52 V"

    So figure out what relay or reason the 12V battery isn't being charged. The DC-DC or maybe some other condition. Maybe clear codes and see if it happens again or if this is all related to ICE stalling.
     
    #3 joedirte, Jun 28, 2012
  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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    This is what attracted my attention:
    The temperature relationship should be:

    MG2 < MG1 < ICE temp

    The first code event showed MG2 well in excess of boiling temperature, 273F. This is dangerously high and even though it looks like outside temperatures were scorching, this is way too high.

    The second one shows evidence the 12V DC-to-DC convert is bad. This is bad news. It also shows MG2 temperature too high relative to MG1.

    Do you hear a low rumble that increases in pitch with speed? Does the rumble remain if you switch into "N"?

    These are the symptoms of failed, MG2 stator, and this is not a trivial problem to fix.

    Bob Wilson
     
    #4 bwilson4web, Jun 28, 2012
  5. joedirte

    joedirte Member

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    Vehicle:
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    Why didn't the engineers put in a cut off red triangle for MG2 / MG1 over a certain temp?

    From the burnt out winding pics and readings of others, it appears the software only checks for inverter overheating, and will gladly let the motors burn up. You would think the software could just shut down until the motors cool off or at least put up a little warning light for various inv coolant too hot, regular coolant too hot, motor/ATF too hot. Did they implement it for Gen 2?


    If I'm reading it correctly, the first code was thrown and the inverter warning maybe because of a self-protect condition... (Not a stall)

    Engine RPM 1184 rpm
    Vehicle Speed 22 MPH
    123-Generator(MG1) Rev 768 rpm
    123-Motor(MG2) Revolution 1280 rpm
    123-Request Power 9120 W
    123-Power Resource VM 304 V
    123-Power Resource IB 0 A

    So that appears to me that based on the gas pedal, the car was requesting to accelerate and all the motors were spinning but IB of 0A means that the HV battery wasn't sending current to MG1/MG2 which were requesting 9kW.


    -------

    The second code was thrown because it was trying to idle and charge up the HV battery, but the ICE stalled or wasn't running. MG1 was matching MG2 (?). I'm not sure what mode this was because the fuel was cut but it was supposed to idle and there is no charge request and the HV battery was sending 16A to MG1/MG2 to spin each other. But somehow the DC-DC wasn't charging the battery. Could this be a code when MG1 is acting as a starter motor for the ICE?

    Engine RPM 0 rpm
    Vehicle Speed 1 MPH
    287-Generator(MG1) Rev 1152 rpm
    287-Motor(MG2) Revolution -128 rpm
    287-Request Power 0 W
    287-Power Resource VM 292 V
    287-Power Resource IB 16 A
    287-Engine Stop Request No
    287-Engine Idling Request Yes
    287-Engine Fuel Cut Yes
    287-Main Battery Charg Req No
    287-Engine Warming Up Req Yes
    287-Auxiliary Battery Voltage 11.52 V
     
    #5 joedirte, Jun 28, 2012
  6. Prius4645686

    Prius4645686 New Member

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    Vehicle:
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    Why would the intake air temp be so high? I'm in Michigan and the outside temp was under 90 F.
    I did notice some haphazardly drilled holes in the side of the intake air filter cover. So, it is likely drawing in most of it's intake air from under the hood. Is this enough to elevate the intake temp that much? I plan to replace the plastic cover and examine the intake duct. Could it be a faulty temp sensor?

    bwilson4web - Thank you for the diagnosis of MG2 stator. I will replace the MG2 stator ASAP, but until then I won't drive it.​

    ​
    joedirte - I think the Inverter goes into a self-protect mode when it registers P3125 and shuts off the DC-DC converter. Disassembly of the original inverter didn't reveal any clear malfunction or damage, so I think replacement was unneccessary. I think the trouble code was probably thrown due to extreme heat as part of the symptoms of the MG2 stator failing.​

    I will replace the Battery ECU too. The battery was replaced about 10,000 miles ago, but the ECU is the original one. Apparently, this is also a common failure after pack replacement.

    Obviously, all the fluids (except Brake) need to be replaced after discovery of this constant over-heating issue.

    Thank you for all the help everyone.
     
    #6 Prius4645686, Jun 29, 2012
  7. bwilson4web

    bwilson4web BMW i3 and Model 3

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    I'm pretty sure the manifold has a water jacket but I agree the intake air temperature sure looks 'funny.' I'll check my shop manual this weekend.

    Holes in the intake box?? . . . Not standard and would explain the higher temperatures. It makes sense to replace the box.

    On the MG2 stator, a short trip around the block can confirm the diagnosis. If MG2 temp exceeds 100C (212F), you'll want to get back to the parking place. If MG2 is burned, you'll see MG2 temperature climb very rapidly as well as the 'rumble.' IF you have time, I need an audio recording that includes calling out the indicated MPH (or MG2 rpm) and the audio rumble while the car is rolling in "N." If you can get it at say 25 mph that would be prefect.

    The reason is we've had others with failed transaxle MG2 stators and the symptom has always been called a 'rumble.' If we could get an audio recording at a constant speed, say 25 MPH, the frequency as well as the audio recording could be used in the future to help the next person with a failing MG2 'get a clue.'

    I understand Lucious Garage developed an MG2 stator replacement procedure. However, I lean towards a used part replacement. IMHO, transmission rebuild work should be done on a bench. But you know your capabilities and can make the best choice . . .

    Thanks for sharing,
    Bob Wilson

    ​

    ​
     
    #7 bwilson4web, Jun 29, 2012
  8. joedirte

    joedirte Member

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    For what it is worth, I don't think IAT 10degF or more above ambient in unusual. You have quite a bit of heat trapped under the hood and especially if the engine is hot and parked in the sun on the hood, the ambient air coming in is heated by all the hotter plastic and metal the air passes by. Especially if you are driving under 30 mph. I've always seen pretty warm IAT especially when it is over 80degF outside.
     
    #8 joedirte, Jun 29, 2012
  9. joedirte

    joedirte Member

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    Model:
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    With an infrared thermometer driving in 95degF air temp for 15 mins, almost everything in the engine was 115degF. All the PVC air intake and box was 115degF, the engine block was over 140degF and the throttle body metal housing with the MAF (and IAT?) was 145 degF.

    I believe the short intake in the cramped engine bay means the intake air gets warmed quite a bit at low speeds. I just cleaned the MAF resistors and the bigger thermocouple I assume is the IAT sensor, so there isn't any buildup on it.

    133 seems high, maybe I check it after letting a hot engine sit in the sun, but I imagine if the ICE was not running, there is no air moving past the sensor, so doesn't seem unreasonable to me.
     
    #9 joedirte, Jun 29, 2012
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