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"Check Hybrid System" after engine swap, no A/C but runs normally

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Tree Soloist, Jun 17, 2021.

  1. Tree Soloist

    Tree Soloist New Member

    Joined:
    Jun 17, 2021
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    Location:
    Mammoth Lakes
    Vehicle:
    2013 Prius
    Model:
    Two
    I think I've checked every thread on this subject. Please be patient with me, I don't have much in the way of money or resources.

    I live in a rural town. The closest Autozone or Toyota dealership is 45 miles away. My friend has an OBD2 scanner that I can access tomorrow, but I don't know if it can read hybrid codes. Also, I live in this car.

    The events: 2013 Prius with 189,880 miles went ~7,000 between an oil change. The oil and filter had silver and bronze colored flakes in it. My friends and I got a donor engine (2013 with ~100,000 miles) and swapped it in. It started up fine.

    Current problems:
    - The dash shows, "Check hybrid system, stop the vehicle in a safe place" and the yellow triangle. Otherwise it runs entirely normally.
    - Also, the air conditioning doesn't cool air when I press the button even though the button turns green. The fan sounds louder when the button is green.

    Already considered:
    - There is plenty of (new) engine coolant and no signs of leaking/depletion.
    - The inverter coolant is also full and getting circulated. The inverter wasn't touched during the engine swap.
    - Inverter coolant and all other fluids were changed at ~182,000 miles.
    - None of the A/C was removed during the engine swap.

    Relevant notes:
    - The engine coolant temperature sensor wires got pulled out of the black plug (the sensor directly behind the large coolant line on the engine's driver side). My friend put the wires back into the plug. I thought they got shorted, so I removed them and wrapped electrical tape around one to separate them, and pushed them back in. They seem kind of loose in that plug.
    - The A/C plug under the hood had coolant dripped on it. I tried to clean both ends out with a rag with the battery disconnected, but upon restarting, the problem was not fixed.
    - The Energy Monitor screen sometimes shows no arrows when the engine or electric motor are in fact running.

    Questions:
    - Ideas for things I can check? How to fix both of the plugs?
    - Is it safe to drive 45 miles to the dealership in this condition, if my friend's scanner doesn't pick up hybrid codes?
     
  2. Tree Soloist

    Tree Soloist New Member

    Joined:
    Jun 17, 2021
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    Location:
    Mammoth Lakes
    Vehicle:
    2013 Prius
    Model:
    Two
    Update:
    I got codes P0351, P0352, P0353, and P0354 - ignition coils A-D, primary/secondary circuit.
     
  3. Tree Soloist

    Tree Soloist New Member

    Joined:
    Jun 17, 2021
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    Location:
    Mammoth Lakes
    Vehicle:
    2013 Prius
    Model:
    Two
    Is there something I'm not including that would get a response?

    The engine temperature light also started flashing when I drove <10 miles at highway speed, or 3 miles up a hill at 20 mph.

    The cabin heater still works.

    I just added more coolant, since it went from "just below full" to "just below low" while sitting for 2 days. There is no evidence of leaking. I bled it by pouring coolant into the reservoir (to B level) while the upper coolant temperature sensor was removed. Then I put the sensor and cap back on, and I ran the car in maintenance mode for 10 minutes with the heat on high. The coolant level is still at B.

    Question: Could the Check Hybrid System warning be related to the engine overheating?
     
  4. ilovegirls

    ilovegirls Member

    Joined:
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    Location:
    San Diego
    Vehicle:
    2010 Prius
    Model:
    V
    You might want to check your oil for coolant if there's no leak and the coolant is going down. Did you check the compression on the donor motor to make sure it was in good condition? The other stuff, I don't know... maybe someone can chime in.
     
  5. ChapmanF

    ChapmanF Senior Member

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    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    The P035x codes indicate the ECM isn't getting spark-confirmation signals (IGF) from the igniters. The four igniters share a common IGF circuit, so when you've got all four codes, that suggests looking for some kind of wiring or connector issue affecting that circuit.

    As far as you are from a dealer or AutoZone, you might want to consider finding a beater Windows laptop and J2534 dongle so you can run Techstream yourself. One thing I'd be tempted to do is look at the engine temperature readings you're getting. There are two, one shown on the Engine and ECT data list, the other shown on the Combination Meter data list. The first comes from the sensor mounted in the cylinder head, and the second comes from the sensor mounted in the hose tee behind the engine. You could look for whether one seems way off compared to the other, as a way to see if your connector repair worked.
     
  6. Roccobro

    Roccobro Junior Member

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    Vehicle:
    2002 Prius
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    I
    @Tree Soloist
    What was the outcome? Don't leave your fellow priusheads hangin'!

    Justin