2002 Prius Won't "READY"

Discussion in 'Generation 1 Prius Discussion' started by jameseroose, Dec 17, 2019.

  1. jameseroose

    jameseroose New Member

    Joined:
    Nov 9, 2019
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    Location:
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    Vehicle:
    2002 Prius
    Model:
    N/A
    Hi - please forgive any improper formatting or my lack of Prius specific vocabulary.

    My 2002 Prius stopped working in late June - no red triangle, just check engine light and no sign of the hybrid system starting (no READY). Pulled codes P0300, P0301, and P0303 with a basic OBDII scanner. The car had a weak 12V battery for a while, and had needed a few jumps in the past. I figured that it had finally gone bad, and planned on replacing it soon.

    Then, I broke my arm and some other life circumstances happened where I couldn't/didn't drive the car for 3 months. I did make sure the 12V battery was disconnected during this time.

    Last week, I got around to replacing the 12V battery with a yellow top Optima battery, installed with a kit ordered from eLearnAid. Car still wouldn't start, check engine light and no READY. Unable to more pull more current codes as they'd been erased when the 12V battery was disconnected and the engine will not start, I observed that coolant wasn't flowing and reasoned that the inverter pump had gone bad. I'd replaced it twice before with spare used pumps I had, but this time ordered a brand new one. Fast forward to today - I installed the new inverter pump, have confirmed that coolant is flowing and can hear the pump working, but the engine still won't start.

    This is where I'm stuck. Should I try following the original codes I pulled in June and replace the spark plugs? The guy from eLearnAid suggested that the hybrid battery could be decharged and that recharging it could fix my issue - I'm not knowledgeable enough to decide whether that's the best course of action, and I'd like to explore other fixes first if possible. Any advice?

    Car has 150,000+ miles. I am able to shift from P all the way to B but no acceleration at all. Sorry if I forgot any pertinent information, I'll gladly provide anything additional that'll help.
     
  2. mroberds

    mroberds Member

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    Vehicle:
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    If you turn the key to "start", and the engine tries to crank but then doesn't start, the spark plugs might help. I'm pretty sure the engine has to be turning, and the plugs have to at least be trying to spark, for one of the P030x misfire codes to set. If nothing else, removing the ignitor coils from the tops of the spark plugs may be useful; sometimes the long "tubes" that go down and plug on to the top of the spark plugs are beat up; sometimes there's an oil leak, and the bottoms of the spark plug wells fill up.

    If you turn the key to "start", and the engine doesn't even try to crank, then I think your problem may not lie with the spark plugs. The engine computer might be able to tell if one of the ignitor coils is bad, and is refusing to crank the engine because of that; it might also believe that one of the other engine sensors is bad (crankshaft position, airflow sensor, probably many others), so it doesn't want to crank the engine.

    It might also be useful to look around all the fuse boxes in the car and make sure all the (12 volt) fuses are good. If one is blown, the car might not have everything it wants to go READY. If you find a blown one, replace it, and it blows again right away, you're at least narrowing the problem. If it doesn't blow right away, maybe that will let you run the car enough to do further investigation.

    This has its own trouble code, but it happened to me: open the trunk and pull the carpet off of the left rear side of the battery to expose the service plug (orange hoop handle). First, make sure the handle is vertical against the battery; if not, that may be your problem. If it was vertical, flip it down and up and down and up a few times, return it to vertical, and try again. There's a microswitch that detects whether the handle is vertical or not, and on mine, the contacts in that microswitch got crudded up, and the car wouldn't go READY. I had to take the microswitch off and blow in it (yes, really!) to uncrud the contacts. Again, there's a specific trouble code for "service plug not latched in", so unless you're getting that code, you probably don't need to get that far into it, but flipping the handle up and down is one of those "cheap, easy, might help" kind of things.

    There are trouble codes for this, too, but another relatively easy inspection: take a peek at all the orange cables coming off of the inverter under the hood, or as much as you can see of them, to see if any of them have cuts in the insulation, or are really covered in dirt, oil, grease, leaves, or other schmutz. Cuts are harder to fix, but clean up the schmutz if possible. You might also inspect the cables that run under the car from the traction battery up to the inverter; these run inside a flat plastic conduit, just inboard of the pinch weld (that metal lip that the jack fits over). You can jack the car up and look, or use a light and a mirror, or even film it on your phone and look at the video. If you ran over a chunk of truck tire or something, and damaged these cables, the car might not want to go READY. Again, there's a specific code for this, but it's relatively easy to make a visual inspection.

    A "generic" scan tool probably can't read the traction battery voltages, but the Torque Pro app with a Prius-specific PID file, and a Bluetooth OBDII dongle, can. Techstream can definitely read these voltages as well. I'm fairly sure you can get these voltages as long as you get some action from the car when you turn the key "on" - the 12 V battery has to basically be working.

    Depending on your appetite for high voltages, it's possible to remove the trunk carpet, back cushion of the rear seat, some of the battery air blower plumbing on top of the battery, and remove the top cover of the traction battery while it's still installed in the car. This lets you walk a voltmeter down the modules and see if any or all of them are really discharged. You have to be comfortable with 300 V DC to do this, though.
     
  3. ChapmanF

    ChapmanF Senior Member

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    Location:
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    Vehicle:
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    Model:
    IV
    Don't use a 'basic' scanner, use Techstream ... as long as you have a good 12 volt battery, if the car doesn't want to go READY for some reason, it will tell Techstream why.
     
    mroberds likes this.
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