More under-side disassembly and visibility

Front under-covers removed There are two separate pieces to the aero plastic under-covers in the front.  The forward one had been off for some time, but now I wanted a good look at the underside of everything forward of the battery pack.  To effect this I raised the front end about as far as I could with my existing scissor-jacks and stands, although maybe I should have hauled out the old red ramps to try for this...  The "oil change carpet" underneath allowed for a bit more comfort while crawling around under there.  Both covers attach using a mix of nuts, bolts, and those annoying little plastic expandy-pins with the plungers.

There's a nice general view underneath the Kona in this video from Edmunds.

Having the forward under-cover off allowed snaking my hand up through the front to disconnect the little alarm-beeper that makes noise when the car gets locked or unlocked electronically.  It's the little green object near the right in the shot of the VESS box between the lights and bumper frame.  It was still a bit hard to get at with the nose of the car still on, as there's a lot of other stuff in the way.  It's totally invisible and inaccesible from above.

View under front: motor/transaxle, pack connections With both parts of the under-cover off, now we can see all of the motor, suspension, and battery connections in all their shiny new glory.  The motor itself is the ribbed left half here, bolted up to the final drive.  The extra round can on the right is the electric A/C compressor.

Battery topology and fact sheet Having a look inside the battery pack would involve dropping the entire thing out of the car, which requires all kinds of heavy-duty lifting equipment, so that wasn't about to happen here.  [Although people *have* accomplished such things in a driveway at home with a handful of jacks and blocks.] I found some nice bits of documentation on it in Techinfo, though, and printed up a nice architecture and fact sheet to display while at the NDEW events.  I added a quick summary of how the capacity is built up, to give a viewer a better idea of just what goes into these things.  There's a much more in-depth technical look at battery innards in an Electricrevs article from late 2018 when Kona sales were starting to ramp up; recommended reading for anyone who likes geeking out on such topics.  A key thing to note in that is not all versions include the heater hardware.

Big battery connector For yucks I pulled out the main battery connection for a look.  It has a big double-locking ejector to help get it in and out of there.  This is supposed to be good for over 400 amps, maybe not continuously but you'd certainly have generous moments of that in spirited driving.  Do the math: 150 kilowatts at, say, 350 volts after some high-discharge battery sag -- 429 amps at peak.

Besides the obvious cooling lines and control harness, the little black square blocked-off plate half-hidden behind the orange hose is where an additional cable for the battery coolant PTC heater wiring would come back out of the pack in the Canadian version of the car.  It's flatly ridiculous that Konas without that and "winter mode" were sold into the New England region.  I believe that Hyundai wised up for the 2020 model year and includes the heater and associated support for all subsequent US releases, at least in the higher trims.


Battery box with PTC heater connection Here's what the same area looks like in models with the battery heater, according to a small shot in disassembly instructions from Techinfo.  The smaller orange wire runs to a module inserted in the cooling lines to the pack, and the relays to energize it are in the pack itself.

  After examining all this stuff I left the covers off for another week to have it all visible for events during National Drive Electric Week, and part of my geek-out display was the carpet in front of the car with a sign taped to it saying "MOTOR!" and an arrow pointing underneath.  You can't see it from above at all, too much other stuff in the way.  Those who were willing to kneel down were encouraged to do so and have a look at this TINY LITTLE thing that could produce 200 horsepower!  I even had the front end jacked up a little to make viewing easier.  All of maybe two people actually crouched down for a look, so maybe that was more trouble than it was worth.  A couple of days afterward I put both covers back on, because I had seen enough under here for the moment, colder weather was on the way, and I did want to try and keep it all cleaner and more protected.


Over the intervening winter, the community started learning some disturbing information about the Kona -- it wasn't the perfect little problem-free EV after all, at least in a few scattered instances.  A recall had been issued for internal leaks in the coolant pumps in some of the cars.  There were growing concerns about motor shaft alignment and reduction-gear bearings, in both the Kona and the Kia Niro.  A few owners reported increasingly loud tapping noises and other symptoms as they drove, and those that took their cars in for warranty service faced a nightmare in getting the problem even acknowledged, let alone fixed.  Hyundai/Kia seemed unable to determine what the problems were, if it was one generic issue or several different ones, and most repair cases endured stupidly-long waits for parts to ship from Korea while their cars languished at dealerships.  It became a game of blind parts-swapping most of the time, and these are major heavy and expensive parts of the powertrain.  And all of that was compounded with the arrival of the pandemic, which forced a lot of this activity to halt for several weeks.

A lot of this fell into a very long thread on InsideEVs, with a surprising number of owners chiming in with "me too"s, recordings of the noise, pointers to other forum posts, and conjectures.  At one point I solicited a quick survey of the affected owners to get a sense of their driving styles.  Here's one problem with this new generation of production electric vehicles: they're too much fun.  That is, with all the instant power they have on tap and far less relative energy penalty for using it, some people love to play!  What's funny is that the Kona is already on the low end of electric vehicle performance -- single motor FWD with decidedly mediocre factory tires -- compare with dual-motor setups from Tesla and the other makers at 400 HP and up, and things can rapidly get, well, ludicrous.  Tesla had not been immune to such problems either -- some of the early model S drive units developed similar rattles and needed replacement.

The Kona's performance is way more than *I* personally need for getting around, so one one hand I could be smug and think gentle driving would prevent such issues from cropping up for me, but perhaps that wasn't actually true if it was an inherent design problem.  Most of the respondents to my mini-poll said they weren't out thrashing their cars in any particularly vigorous way, and some drivers did seem to eventually get things fixed with motor *and/or* gearbox replacement.  And possibly a dash of luck, as precise parts alignment on assembly seeemd to be a critical aspect of the design.  I think the conclusion was that *some* of the drive units were just shredding themselves internally no matter what, so like with the virus, symptoms were highly random across the populace, and everyone just bumbled on with life hoping that it wouldn't happen to them and that there would eventually be a real answer.

As the next Spring arrived I wanted to get back under there for a more detailed look at some things, especially after reading some of the TSBs and stories that had emerged.  I wasn't about to drop motors and transmissions, but there were other things to collect information on and the under-cover had to come back off first.  This time I drove the car up onto ramps, which was quite a bit easier than wrestling with pairs of jacks and stands.  So our tour continues...


View directly under motor We're looking straight up at the motor from underneath.  The round indentations are freeze plugs, and are also present on the front and back.  This hints strongly that the fatter parts of the housing are the cooling jacket, which is presumably isolated from where the stator fits into the casting.  That doesn't leave a lot of room for stator diameter!  It's kind of amazing that this unit is good for 200 horsepower.

Motor coolant lines The coolant lines run in and out of the jacket on the front of the motor.  The pipes passing by underneath are refrigerant lines to and from the compressor.

Vent hole at flange bottom At the bottom of where the motor bolts to the reduction gearset, there's a small weep hole similar to what's on most transmission bellhousings.  Looking up into it with a strong light doesn't reveal much but I can glimpse just a sliver of motor shaft passing through between bearings.  The hole is too small to work a borescope up into -- no matter, as there are disassembled pictures of what's in there in the referenced forum thread.

Passenger end of the motor The passenger end of the whole motor.  The position resolver would be under the smaller endplate, and its connector comes off the front of the unit.   Note the aluminum-oxide corrosion on some of the motor housing already -- after only one winter and not a lot of driving in slop.  What'll it look like in five years?

The coolant pump for the battery loop is mounted behind the drive assembly where the arrow points, and that whole area around and above it is a maze of plumbing.  The other pump is on the front, servicing the electronics and motor.


  Both pumps wanted a close inspection, because one symptom of the internal coolant leak is corrosion showing up on the pins of the electrical connector.  I unbolted the brackets for both so I could move them around a little for better visual angles -- much easier to do from below than above, although wrenching ultimately happened from both directions.

The pump problem affected the Kona and Niro, as they use some of the same parts.  For this there was an actual recall with diagnosis and fix instructions, and although the TSB for the Kona didn't mention manufacture date windows affected by it, the Kia TSB does.  My vehicle's placard date fell *just* past the window which ended in January 2019, and the Hyundaiusa website didn't show anything outstanding for my VIN, but I wanted to see what they were on about and make sure there was nothing obvious to see.  I could collect more geeky pictures, at any rate.


Coolant pump connector Nothing untoward going on here; both pump connectors look fine.

The pumps are actually CANbus nodes, and the 4-wire harness brings them power, ground, and network for control.  That means they can't be run for diagnosis or coolant system bleeding by simply applying voltage or the like, they have to be issued actuation commands over CAN.  Not having a handy way to do that or the knowledge of what the command packets consist of is a prime motivation for *not* draining the coolant system and actually removing the pumps for bench inspection.  Otherwise I'd have to go crawling off to the dealer and beseech them to plug in their GDS and do the bleeding procedure.

Insert big "right to repair" rant here.


Front water pump: motor, electronics Rear water pump: battery cooling
    motor / elex     battery
That was okay, I could keep all the plumbing intact and just twist them around enough on their connected hoses to see what I needed to see.

The two pumps look very similar but are actually different part numbers, and apparently able to sprout the same internal leaking problem in certain instances.  The 201902... part is the date code, again here placing the *pumps* later than the targeted manufacture dates in question.  OS is the model code for the Kona, and DE for the Niro; and the labeling even indicates the purpose of each pump -- probably "power electronics" on the left, and clearly "battery" on the right.

Interestingly, powering up the car with the pump connectors disconnected doesn't throw an immediate error; the system may only worry about their presence when it tries to actually run them.


Motor flange bolts seem adequately long A TSB about using longer bolts for mounting the motor made me curious what's up with that.  All the bolts seem adequately long here, they come through to just flush with the other side of the reducer flange.  I gathered later that some *replacement* motors have a thicker flange and using the original bolts would compromise the threading strength.

Fill and drain plugs for reduction gear oil Back by the drivers-side axle we see the fill and drain plugs for the gear oil.  I wanted to check the color of the oil without having to drain it, as a dark, opaque color would indicate presence of wear metals.  With the car slanted upward on the ramps a lot of the oil would be piled up here at the back, likely well over the level of the fill plug, so simply opening it up to dip out a sample would have made a mess.

I cracked it open just a little bit, though, so oil could slowly seep out past the threads where I could dribble a sample onto some white paper.  The plugs need a 24mm socket.  Conjecture is that the lower one has a magnet to collect shavings, but we won't know until someone actually drains the oil and reports.


A quick oil sample from upper plug The sample is actually quite clean, not bad for a little shy of 5000 miles at this point.  Maybe my gearbox will be okay.

The paper is a piece of yet another mailing from Sirius XM, which regularly spams me with re-subscription offers since I let the dealer freebie lapse.  They can still take a powder.  I am *so* glad I never gave the dealer any email address.


  [ Up to EV index ]

_H*   191007