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Red Triangle + Power Steering Errors

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Hasan, Aug 11, 2017.

  1. Hasan

    Hasan Junior Member

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    Hi all,

    My 2007 Prius with ~120k miles has recently (last month or so) been throwing up all sorts of weird errors including the Big Red Triangle and ABS, VSC icons. The problems are intermittent and seem to have no pattern or logic. I suspected the 12V battery, however, this was replaced in April 2016 and I checked the voltage just now using the MFD diagnostic menu with the car in ACC mode, the voltage was 12.4 which looks healthy?

    The car has now started to produce a power steering error with p/s on the MFD, whenever this appears the steering becomes very stiff with no electrical assistance. This is also intermittent and occurs every other day or so, switching the car on and off usually results in the problem going away.

    I ordered a mini VCI and pulled some codes, screenshots attached below. I pulled the codes twice and seem to have got differing results as the initial try had two HV related codes, P3000 (very worrying) and P0A84, but these completely disappeared the second time round! I have not noticed any issues with the HV charge rate, no rapid charge or discharges as suggested may be expected from a faulty HV battery.

    I have done quite a bit of googling and searching on this forum but am not really particularly wiser as to what is going on with this car. I have googled all the codes and come up with the following but thers seems to be an awful lot of codes, what's the actual problem? Surely, this car cannot have all of these issues when it's been working perfectly up to now. I have owned this Prius since Feb 2011 and it has been maintained at the dealers every year without fail.

    P3000 - HV battery malfunction
    P0A84 - HV battery cooling fan error
    C1378 - Skid control ECU
    C1378 - Capacitor Communication Malfunction
    U0073 - Control Module Communication Bus OFF
    U0123 - Lost Communication with Yaw Rate Sensor Module
    U0124 - Lost Communication with Lateral Acceleration Sensor Module
    U0126 - Lost Communication with Steering Angle Sensor Module
    U0129 - Lost Communication with Skid Control ECU
    B1630 - Driver Side Rear Airbag Sensor Malfunction


    Should my first point of call be replacing the 12V?
     

    Attached Files:

    #1 Hasan, Aug 11, 2017
  2. bisco

    bisco cookie crumbler

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    12.4 is on the line, especially for a newer battery. you may want to have an amperage check done.
     
    #2 bisco, Aug 11, 2017
    Hasan likes this.
  3. dolj

    dolj Senior Member

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    P0A84 = Hybrid Battery Pack Cooling Fan 1, and could be the reason for the P3000 which is a general failure code.

    I'd be inclined to inspect the HV battery cooling fan and check it runs (can be turn on to all speed settings with TS) and check whether the fan is clean.

    I'd be less inclined to focus on the 12 V battery, but an easy way to verify that would be to find a known good and fully charged 12 V battery and attach it to the car on the jump start terminal in the engine bay with jump cables (pay close attention to the polarity – do not get this wrong as you will cause multi thousand dollar damage).

    You may want to check the wiring looms that connect the ABS and VSC ECU's to explain why you are getting so many comms errors. You also can get comms errors when a cheap OBDII cable is used.

    I'd focus on the HV battery cooling fan as the main DTC.
     
    #3 dolj, Aug 12, 2017
    Hasan likes this.
  4. Hasan

    Hasan Junior Member

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    Thanks, I did come across other posts about corroded wires at the back of the car etc. Will have to strip the back lining and take a good look at those, I can check the HV cooling fan at the same time. Now to find a quiet weekend to do that...argghh

    Nexus 6P ?
     
    #4 Hasan, Aug 14, 2017
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