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2006 Prius DTC P3102 troubleshooting

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by garym, Jun 8, 2018.

  1. garym

    garym Junior Member

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    Hi Everyone,
    I am new to the sight so I hope I am posting in the proper place for the info that I'm looking for. I have a 2006 Prius with 260k mi and the transmission will not go into park. I have verified the 12v battery is good and can't find any obvious wiring or corrosion issues. I have however found a stray voltage issue while using the flow charts for testing the wiring between the HV ecu and the transmission ecu. The manual tells me I should have less than 1 volt on the white wire (pin #8 on T4 conn at tecu, & pin #10 on H17 conn at HVECU ) but I have 10.5 volts. The flow chart only tells me to correct the wiring or connection issue , unfortunately I don't know where the issue is coming from.
    Does anyone know where else the white wire that I mentioned could be getting the 10.5 volts from? I have unplugged the park module on the transmission and removed the 7.5amp fuse from the Pconn motor but the stray voltage is still there. Thanks in advance as any help or guidance will be greatly appreciated!
     
  2. garym

    garym Junior Member

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    Update: I did find the problem/cause of the P3102/C2300 codes and the P-lock warning message that came with them. after checking all the simple and obvious possible problems I started ohming out the circuits involved and found to much resistance in the lt green wire that runs from the shift control actuator on the back of the tranny to the transmission ECU under the glove box. I tugged on the wire at the S1 connector (actuator end) and the wire pulled right out. The only thing that I can think of is that it had a poor crimp from the factory because the wire was broken inside the connector.
    Hopefully this info will help others with same issue. If you search those codes and troubleshooting the problem there are several wiring diagrams and flow charts available online to help. I have read a lot of posts that say to start by replacing the battery or ECU's, but you should do you homework first. It will save you some money and unnecessary replacements!

    PS- toyota sells a repair terminal for the connector that is pre-made (82998-24250) and readily available , so I think its a pretty common occurrence.
     
  3. bisco

    bisco cookie crumbler

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    welcome and thank you!(y)
     
  4. Rogelio Torres

    Rogelio Torres New Member

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  5. Rogelio Torres

    Rogelio Torres New Member

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    Hi,am working at same codes,is hard access to shift control actuator o conector?
     
  6. garym

    garym Junior Member

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    Yes it is difficult to access the actuator because it is located on the back side of the transmission close to the firewall. I removed the engine cradle and steering rack to get to it. Also the wiring harness is short on the actuator end, so for me that seemed to be the best option. Good luck!
     
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  7. Devin Perry

    Devin Perry New Member

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    Thank you so much for posting this. I’m getting the same code and p lock message too. Lol sounds like you’ve dug deep into this issue so I’m going to give your solution a shot
     
  8. Figster10

    Figster10 Member

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    /


    So it sounds like you ended up replacing/repairing a bad connection on the green wire from shifter actuator sensor to transmission ecu but is that something you can confirm worked??

    I think this is my issue because I had the same code(s) that brought me to replace a bad shifter actuator because it was literally snapped off leaving it to keep spinning on the transmission. I replaced it and maybe 1,000 miles later same codes you got returned. Codes pop up every 40-120 miles now.

    thanks for your help just need to know what to look for when I do pull the harness down
     
  9. Figster10

    Figster10 Member

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    Did you have any success with this issue?
     
  10. mr_guy_mann

    mr_guy_mann Senior Member

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    I assume you have a P3102 set by the hybrid control ecu. What codes are in the transmission control module? What are the INF subcodes? That will determine what circuits you need to focus on in the procedures in the service manual.

    Posted via the PriusChat mobile app.
     
  11. Figster10

    Figster10 Member

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    I am on my 3rd shifter actuator in the span of 5,000 miles now.
    codes prior went to C2301,40,10 and then normally this round on my 3rd shifter actuator shows P3102, 582 every 40-120 miles now. I have replaced the transmission ecu and checked for bad grounds on the engine with no issues.

    I have my mechanic scanner and I do notice on a freeze frame that the the 3 phase readings show the following:
    Phase U 0.15v
    Phase V 12.96v
    Phase 0.31v
    which is very off considering all 3 must be 12.00volts and higher.



    I also notice my parking shifter learning continues to say NOT GOOD prior to giving me transmission ecu.

    So on a live data it looks like I have issues somewhere with the shifter actuator and transmission ecu.

    The first shifter actuator for some reason was cracked and replaced but nothing changed.

    2nd shifter actuator began giving random codes c2301/40/10 and P3201, 581

    I have the repair guide and I am at almost everything it tells me to do with last resort being to replace the shifter actuator AGAIN. If this doesnt fix it maybe replacing the harness might fix it but I see nothing wrong with it nor are the voltages from transmission ecu showing anything.

    I have exhausted just about everything the repair guide suggests.

    next would be ecu's being swapped out but I doubt that will help
     
  12. Figster10

    Figster10 Member

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    part 2.
    I also do not always have success using this repair guide and sometimes fix things on my own contrary to what repair guides suggest. There are times it ended up being something else other than what repair guides have sworn to be the issue, I will continue to check things out and replace other components for now.

    I am only asking here to see if anyone found something else to be the problem outside of what repair guides are saying
     
  13. ChapmanF

    ChapmanF Senior Member

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    Are we talking here about the repair manual where the people who built the car tell you how it's built, or some other kind of repair "guide" from somewhere else?

    I agree the internet is awash with repair "guides" that often lead to goose chases.
     
  14. Figster10

    Figster10 Member

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    the toyota repair guides. I have had success with the guides but i have also had many situations where they didn't really help at all.

    All I'm suggesting is sometimes the repair manual guides don't help. I own 9 of these cars and fix a lot on my own selling a lot more for my business and sometimes I get stuck like with this particular situation.

    I am on shift actuator #3 within 5,000 miles and have come to the conclusion that possibly the transmission or a bad ground somewhere is messing up my shift actuators.

    I have a lot of experience with the gen 2 and some with gen 3 but this problem is a tough one
     
  15. ChapmanF

    ChapmanF Senior Member

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    True, the troubleshooting steps in the manual sometimes call for an active-reading approach: "why are they telling me to test these things in this order, what does that tell me about how the car is built, and how does that help me interpret what I'm seeing, beyond blindly following some steps?"

    One of the best examples I've noticed is in the engine disassembly / reassembly steps, where they very carefully tell you to move the crankshaft at least 40° away from TDC before moving the camshafts at all with the timing chain off. They never straight-out say "hey, we built an interference valve train, you need to do this so you don't clobber the valves"; you just have to infer that from what they do say.
     
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  16. Figster10

    Figster10 Member

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    mechanically the repair guides are spot on and have helped me with engine/tranny swaps.

    I think when it comes to electrical or hybrid issues it can be a headache to follow because like most electrical issues it can be 1 of 100 possibilities.

    I will drive 1,000 miles with my third shift actuator in 5,000 miles and see what happens.

    the next thing to do here would be to replace harness but I honestly don't see anything wrong to call for a new part. I've never had to replace an ecu on any prius I've worked on unless water damage or totally fried due to low 12v battery beating it up.

    I WORK ON A LOT OF GEN 2'S AND GEN 3'S HERE IN THE BAY AREA SO IF ANYONE HAS ANY QUESTIONS ABOUT THE CARS FEEL FREE TO MESSAGE ME