Honda IMA Motor Fail. CR-Z, Insight. P15A5 Motor Current Circuit. IMA HV resistance to ground fail! скачать в хорошем качестве

Honda IMA Motor Fail. CR-Z, Insight. P15A5 Motor Current Circuit. IMA HV resistance to ground fail!

CR-Z with suspect IMA motor leaking to body ground and no/low voltage across one of the phases when tested with 110V Incandescent bulb. Bulb testing reveals direct/strong connection to body ground!! Note. I mistakenly state W phase is shorted to ground. It's actually one of the others as otherwise the bulb wouldn't light. It's not vital the motor has come out anyway now!! Dodgy Dealings!!! "It only needs a new 12v battery mate.." This actually translates into it's properly fuc**d. 😡 UK owner only had car a couple of weeks and put a new 12v battery on it as advised by previous owner. IMA Light on code P15A5. 😭 IMA not working and 12v battery dying as expected. So it's been brought to me on a recovery truck. Honda advised buying a non refundable £300 phase sensor array which did not fix the issue! 🥺 It is an interesting but sadly expensive fault so here are some details. If you clear the code it goes away and does not come on with just the ignition turned on. The IMA boots up correctly after a reset and all the contactors engage. The IMA system is ok/happy at this point. (Engine off) The code only appears when you attempt to start the car. You can hear the IMA motor trying to do something feeble for a couple of seconds then it faults and falls back on the 12v starter. Ok The advanced diagnostic title for P15A5 says "Motor Current Sensor Circuit Malfunction." That title is a bit miss-leading IMO and leads you to suspect the phase sensors are faulty. This is what Honda did and the poor customer ordered a new set for £300. It is actually an overcurrent situation as detailed later in the diagnostic info .. So what causes overcurrent.... Lower resistance than expected or short circuits. In deference to Honda initially I did change the phase sensors which made absolutely no difference. After swapping out a few other modules including the MPI I was getting suspicious.. Crank up the HDS get a full data list printout and hmm something is very odd.. The High Voltage IMA to body ground resistance reading is 0k ohms and it should be over 400k. Hmm.. That should trigger a different code I wonder why it hasn't. Perhaps it takes a few drive cycles and is not immediately fatal. (Have to look into that later) OK so it's overcurrent, the phase sensors and MPI are good so I wonder what the motor phase winding resistances are?? Cue the multimeter and oh horror, the IMA motor is shorted directly to the body ground and the HDS reading 0k is correct. I tested directly at the motor connections on the engine block, so we know it is not the orange cable, which can get crushed underneath the car by bad jacking practise or road debris. It's a very unusual motor fault and the resistance of every phase winding is well below 1R so I suspect the motor is shorted internally to ground. How that has happened won't be known until it has been removed and examined. (Note the windings do have a low resistance normally) I suspect a bolt or something has come out and been hurled around inside the motor housing damaging stator windings and perhaps wedging itself into such a position as to create a body short!! Apparently it had a recent clutch job?? Flooding is another possibility... We have seen one other failed IMA motor where stator bolts came out. The stator shifted position and the rotor contacted the stator causing massive friction heating and meltdown. In this case he got the isolation fault P0AA6 rather than the P15A5. The G2 Insight uses the same IMA motor, but I can't recall if the housings are identical. If not the stator can likely be transferred to the CR-Z housing.