The Cheapest Car In The World (The Changli) Is Broken And I’m Stumped

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I want to preface this by reminding everyone that overall, my Changli, the Cheapest Car In The World, has been incredibly reliable. After about a year and a half of ownership, I’ve only really had one breakdown, and I was able to fix that with some electrical tape. This time, though, there seems to be something more significant going on, and I’m a little stumped.

Last week, the Changli was doing just great! David was by for a visit, and my kid Otto and David and I drove that little 1.1 horsepower Chinese electron-burner all over town. Zero problems, just good, honest Changli fun.

I was in Detroit for a week, and when I got back and wanted to take the old ‘Li out, I was met with a pretty basic problem: It didn’t want to move. And moving is something that I personally think is a real desirable quality in a car, even if you wouldn’t necessarily know that from looking at my driveway.

It turns on fine, dash display comes on, the voltage shows the expected number of 63 volts, but when I attempt to drive, this happens:

Hear that weird pulsing? It sounds like some kind of strange, intermittent short, maybe? Like the motor is being stopped and started over and over. I checked back at the motor assembly itself to confirm, and that’s what it seems to be doing: pulsing on and off, I think. Here, look:

It’s funny to me that I still asked my kid to hit the “gas” even though, of course, there’s no gas involved here. The sounds and motion do kind of remind me of a poorly-running small gasoline motor, but that’s just a silly coincidence.

I checked the under-seat battery area again, where the problem was last time, and did find some evidence of a similar issue to what happened before, in the Changli’s one breakdown:

Something is still causing this wire bundle to heat up and melt things and cause problems. Last time it just melted its own tape off and came disconnected; this time, because of my better-than-factory twisting and taping skills, the bundle stayed together, and instead actually got hot enough to melt through the plastic battery handle, which isn’t great.

The picture up there shows the condition of things after I un-taped and disconnected things. That revealed this:

So, the heat had melted the insulation, and two close wires ended up with bare wire touching, causing a short. I thought this had to be the issue, so I got everything apart, cleaned up, taped up the exposed wiring, and figured that’d be it, but no luck. Still the same pulsing behavior.

So, now I’m wondering if maybe the short fried something in the motor controller? And, is the motor being pulsed on and off, or is it possible it’s getting polarity reversed over and over?

I tried in forward and reverse, and each time I got a small motion in the selected direction before the rhythmic pulsations began, so I think it’s at least moving in the right direction.

I’m not exactly sure how to diagnose this; I suppose I could try to put 63 volts directly to the motor and see if it spins normally, bypassing all of the controls in between, and confirm that the motor itself is okay.

I can also open up the controller and look for obviously burned/charred/etc. components. I didn’t see any smoke coming from them, or smell anything too odd, though as I type this I think I recall smelling something as we drove last week.

But, like the legendary ads say, it ran when parked. What changed? It’s been pretty wet here, and water conducts, so perhaps that was a factor?

I may try to reach out to Changli, too. After all, they kinda owe me for all the good publicity I’ve given them, after all. They even have me on their Alibaba page. They can at least hook me up with a motor controller, right? I mean, if that’s what this is.

So, right now, the Changli is just an expensive bed for my cat, Tomato:

It needs to be more than that, I think. If there’s any electrical or EV engineers out there who may have an idea how to best diagnose or fix this, I’d love to know! Tell me in the comments, and if you need more pics or video or whatever, I’ll get it to you!

I use this silly thing a lot, I now realize. I want it running again!

135 thoughts on “The Cheapest Car In The World (The Changli) Is Broken And I’m Stumped

  1. A great and little-appreciated benefit of being a popular automotive writer: 101 experts at your beck & call for the odd car problem — or is that: a problem with an odd car?

    BTW, in my uneducated opinion, the electrical guys have a much better and more fully-developed diagnosis than do the mechanical types. (Check the batteries first.)

  2. My god, David lives on rust and ATF, and Torch hasn’t washed a car in years. No wonder the xB is a Petri dish. Perhaps hire a tall person to wash the roofs of your cars. Poor VW Beetle.

      1. I have seen mung like that in Oregon. Yeah, pollen makes cars instantly dirty, but what I see is base neglect, a combination of dust, biofilm, pollen, mildew…
        The Scion xB. It grew stuff on the interior. Gross.

        1. Agree that the Scion was gross. I guess I just was looking out in my driveway and feeling a little guilty about how the exteriors of my vehicles are looking right now.

  3. When a friend of mine was studying to be a motorcycle mechanic 25+ years ago, he used a book. to help him understand electricity. This book recommended viewing electricity as little green guys chasing little green girls. Perhaps your little green guys and girls escaped.

  4. So now, in addition to worrying about DT catching tetanus, we have to be concerned about JT getting electrocuted.

    Be safe out there guys…

    Unrelated and only half joking. How many miles is the manufacturer’s warranty for this thing?

  5. 1) I wouldn’t trust any of the high load carrying cable you’ve pictured – the insulation is damaged quite badly. It needs to be re-wired with good copper wire.
    2) A good (or cheap) IR camera would help some diagnostics with bad connections if you’re not handy with a DVOM – Given the projects on the site it may see a lot of use?
    3) What changed was probably the carting of 3 people vs the standard 1 or 2 – you likely pulled a LOT more current from the batteries in your jaunts about town. High current and temperatures would make the batteries, wiring, motor, and controllers the first place I’d start poking about.
    4) Be careful with the 60V+ system – do a quick amount of research – this is is not considered low voltage (which is less dangerous). We all want more non-hospital related content.

      1. According to your own link – not if you ask the NFPA, NEC, and UL.

        Assuming we’re dealing with the US. Though I imagine the Chanli isn’t UL listed.

        1. Odd since the NEC article claims 100V is the cutoff:

          The electric code makes a distinction between “high” voltages above 100 volts, and “low” voltages below that. For circuits defined as low voltage, in some jurisdictions, there is no requirement for licensing, training, or certification of installers, and no inspection of completed work is required, for either residential or commercial work. Low voltage cabling run in the walls and ceilings of commercial buildings is also typically excluded from the requirements to be installed in protective conduit.

          The precise reasoning for the selection of 100 volts as the division between high and low is not clearly defined, but appears to be based on the idea that a person could touch the wires carrying low voltage with dry bare hands, and not be electrocuted, injured, or killed. This is generally true for 12 volt systems, but becomes more ambiguous as the voltage increases to 100 volts.

          https://en.m.wikipedia.org/wiki/National_Electrical_Code

          But I guess it even then it depends:

          even within the NEC, the term “low voltage” can mean anything from less than 600V, 50V or less, or less than 30V depending on the section you reference.

          https://www.securitysales.com/contributed/power-is-knowledge-how-nec-pertains-to-low-voltage/

          I imagine UL and NFPA are the same way.

  6. Have you tried checking the blinker fluid levels Jason? 😉 ive missed seeing content from you and the lover of rust David Tracy since leaving Jalopnik.

  7. I remember that my Power Wheels did the exact same thing when the batteries died. Remembering back 34 years when I was 4 or 5.

    POW POW Power Wheels POW POW Power Wheels!

    1. I remember we burned out the motors on my Power Wheels, because you weren’t supposed to use it on grass, then we wore through the plastic wheels, because you weren’t supposed to use it on pavement

  8. Look it’s a used car, do the smart thing. Sell it for 25K, order a new Changli for 2K, wait a few months for it to arrive and you’ll come out way ahead, Heck, you could even start a fresh series about the new one. Content!

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  9. i guess i should explain the noise.. if your battery(s) have a dead cell, when you attempt to move the car you apply a large load to that battery back, the voltage drops precipitously, which will cause the motor controller to drop out, then voltage recovers once the load is no longer there. wash, rinse, repeat… you should be able to see that on a scope (if you have one) or a multimeter connected to the power input to the motor controller. you can also pull and test each of your batteries. they look like 12V SLA, so you can take them to an auto store and convince them its a lawnmower battery. in all likelihood your motor and controller are fine. first rule of electronics diagnosis, ensure your power is fine before suspecting anything else.

    1. Okay! I have a voltmeter, but how can I use that to test for a bad cell under load? Because they’ll all read 12V when sitting, correct?

      1. yes, provided its quick enough to register the changes. you can do once battery at a time to figure out which one it is. also… you can lift the drive wheels and see if it can spin those at all. if it can, its almost certainly a battery/power issue.

        1. perhaps a more fun way to diagnose the batteries is with a sealed beam headlight. i know you have one, probably hundreds. you can connect one to a single battery and see just how quickly it gets dim. if the a SLA battery has a bad cell it’ll usually go dim(mer) in less than a minute, while a healthy battery will be able to power it for quite some time.

          1. This. The sealed beam headlight is a trick worth trying as it doesn’t take a lot to set up and just works. If it all seems good, then move onto the more difficult fix attempts. Good luck!

      2. Suggestion: use a multimeter to measure the resistance of each battery. They should all be close. If one of them isn’t similar to the others, it likely has a bad cell. You will need a large resister. There are guides online on how to measure this.

        https://www.instructables.com/How-to-measure-the-internal-resistance-of-a-batter/

        Alternatively, you could have the drive wheels lifted, and see if it spins under light loading. If so, find a way to keep the load steady(perhaps a brick under the accelerator), and look for consistent current/voltage values. While putting it under load, measure each battery’s voltage. If one of them drops to a lower voltage than any of the others, you’ve found a battery with either a bad cell or bad connectors/cables.

        1. i approve of this method. though i dont know how much electronic junk (that ISNT video game consoles) that Torch has in his basement.

          1. A cheap $8 multimeter from Harbor Freight or some other crap hardware store will do the job.

            A friend of mine converted a Mazda B2200 to electric back in 2010 and had a similar problem. The truck would see a massive voltage dip and then shut off even under light loading. I immediately knew that it was a high likelihood he had a bad battery. We located the bad battery, removed it from the series string, and the truck ran as good as it used to. It was a 168V conversion using Marine batteries, and we dropped it to 156V, so the performance loss wasn’t noticeable. It also had no BMS. I advised him that he was also using the wrong kind of batteries for the application and to replace them ASAP, which he did. Unfortunately, that truck got totaled 4 years later by some yuppie wrecklessly test driving a Porsche who broadsided it at a high rate of speed.

            If Torch has a bad battery and locates it, it is very likely the Changli will still run with it removed, depending upon the minimum voltage parameters the controller is set at. Although, he’d want to replace the bad battery ASAP, because his range will be crap(moreso than it normally is) before the controller and/or BMS shuts off. And it shuts off to prevent damage to the transistors and other components. Being that the batteries in the Changli are lead acid, and a single series string, it really shouldn’t need a BMS.

            1. >> yuppie wrecklessly test driving a Porsche

              The yuppie wasn’t wreckless after totaling your friend’s car (I think you mean “reckless”).

            2. I cannot imagine the oem Chinese batteries being a pillar of durability, being over 1 year old. Maybe need some Optima batteries…

              Time for some mods….

              1. Isn’t the Autopian “powered by Optima?” This seems like a great promotional thing. Get an Optima rep out there, make a video, talk about differences in battery types and quality. Involve your sponsor! And slap a “Powered by Optima” sticker on the Changli.

                1. this is absolutely the right approach. this would be a great way to involve your sponsor in the story, get the changli up and going, and increase its performance/endurance/safety and create a bunch of content at the same time. everybody wins here.

                  1. With any luck, the battery company will donate a full set of new batteries, some very thick copper cables and a technician to assist with their installation. A new Autopian article would then practically write itself.

        2. A broken battery will show an infinite resistance and 0 voltage.

          Now seeing how burned the cabling is, I’d recommend to replace all the power cables by cables from a bigger gauge.

          If a cable heats enough to melt it’s insulation it means that too much power ( amps ) for the gauge is going through the cable. ( I burned a few at university learing about electrical motor powering long ago. )

      3. Disconnect all the batteries and check the voltage on each one. They should all be within +/- 1 volt of eachother.

        If one is way off, that’s your dead battery.

        If it this tests normal, put the voltmeter across all the batteries and note the voltage. Try the go pedal, if the voltage drops more than 20%, all the batteries are toast.

        Even if it looks like only one dead battery, I’d replace them all. If you do decide to only replace one, make sure all the batteries are charged to within 1 volt (after sitting for an hour off the charger). You’ll make the batteries much happier this way.

      4. Let me reiterate the importance of getting that wiring sorted out safely. Simply put, that car is a fire hazard, and your insurance company will find your blog posts if things go south. There is enough current in that little BEV to weld. If you’re uncomfortable sorting out that wiring mess, I’ll gladly help you do a proper job, even if that means flying out to that sweatbox you call home. You are too valuable to cheap out on the world’s cheapest car. rootwyrm is basically correct, if not a bit alarmist. you may very well have dead batteries, but that wiring is a one-way ticket to a blog post titled “the world’s cheapest car destroyed everything i own”

        1. When I was a little younger I used to race 1/10 scale electric remote controlled cars. They run on 7 volts and would have spontaneous combustion of the electronics if they were not sorted correctly. Toledogeek is absolutely correct here. That wiring is a disaster and makes me nervous for your cat.

    2. This is where my head was at also. Voltage is dropping off a cliff, thus the capacity meter goes down, and it has no power to move the car. I do not think this is mechanical. It’s electrical.

    1. Or the drive gear is rounded off, so each time it slips, it pulls too much current, but doesn’t move the wheels. Lotsa vibes too. I’d open up the drive unit.

  10. that wiring looks rough, not to mention unsafe. you should really separate the positive and negative wires in that loom from each other before they start a fire and burn your house down. use some split loom if yer feeling lazy. or just rewire it properly..
    the battery casing is showing some warping, so i’d suspect that you have a battery with a dead cell. the voltage will look fine but drop a ton when there is a load. i also suspect that you left it on the charger while you were gone, which could have boiled the electrolyte right out of it. need more photos!

    1. I didn’t have any idea except take it to your local Changali dealer. Hey one year must still be under warranty. But this comment reminds me of an issue I had with my ICE when doing some wiring on my JH had the wiring melt the 2 wires together in several places. I found and fixed 1 but still had the problem more investigating showed 6 spots where pos/neg had melted together.

  11. Don’t connect the motor directly to the 63 volts. You’ll either get hurt or you’ll burn something up. The motor controller is there for a reason.

  12. If the motor were simply pulsing on and off I’d expect to see slight movement of the vehicle. This looks and sounds like something may instead be physically broken in the drivetrain and you’re getting a chattering of broken metal against broken metal. If you separate the motor from the axle unit, you may be able to check whether (1) the motor then spins normally when power is applied and (2) any damaged components are visible. At least that’s the first thing I’d check.

    1. Torch, I’d check the possibility of mechanical failure as per the above first, if possible. If anyone can diagnose a fault in a ‘so bad it’s good’ car and get it running, it’s mdharrel. (seriously – check his collection. Please. I beg you. You will want to thank him for keeping the unusual and mostly unloved, alive. Well in various states of semi-functionality at least. Which is the best sort of functionality I think you can hope to achieve when you’re talking… the sorts of cars for which mdharrel has an affinity.)

      Just be very careful, there’s potentially (see what I did there) very high fault currents running around those things.

      If it’s not the above mechanical issue, then it sounds as if the controller is fried. Electrically speaking, an electric motor at zero RPM is a dead short. Put an electric motor under load straight across a battery/power source without a suitable controller or resistor, things tend get hot or go bang – usually at the battery end. That’s why controllers exist in application where high loads or variable speeds are required.

      Which is why my take – if the problem turns out to be electrical – is that the controller is no longer able to control the power to the motor adequately. I think maybe it’s overloading then shutting down with every attempt to send current to the motor, then trying again, then shutting down, trying again, shutting down etc. – hence the ‘chattering’ that you’re describing.

      1. Editing to add another (again electrical) possibility – when the battery voltage drops that much when under load, it’s can also be a sign of a dead battery cell. It’ll show full charge with no/minimal load, but the higher internal resistance of the battery means that the voltage drops a lot to try to deliver the required current for turning the motor.

    2. Yeah, this is something I would look into as well. It certainly sounds like a gear or a spline is slipping. In the video posted your speedometer claims that you are moving when sitting still possibly supports this (I’m assuming the gauge reads the engine speed).
      Though I wouldn’t doubt that there is something possibly wrong with the electrics as well, based on the overheating wiring.

      1. Yeah, none of the other theories explain the bogus speedo reading. _Something_ in the drivetrain is moving fast enough to convince the car that it’s doing 24 kph.

        Which, incidentally, is probably the fastest 0-24 run a Changli has ever done, even if it is complete nonsense. 😉

  13. The BMS could be toasted from the short or the motor controller itself. From the way its acting and still turning on I would think the motor controller. You could test for appropriate voltage. I think if its toast then you buy a wrecked model 3 and drop that drivetrain in the Changli.

      1. This is my guess. I totally get it sounds like a starter with not enough power just clicking, but if that were true you’d think the whole car would shake. The fact that the motor is shaking but the car isn’t moving to me means the chain is broken or something stripped and is beating around in there.

        1. Considering the provenance and price of the vehicle, the failure of a critical metal part while under stress, due to a lack of tempering, is likely the culprit. Murphy says that it will be in the most mysterious to diagnose and difficult to repair location*, so try that spot first.
          *for which replacement parts are nearly impossible to locate

    1. “You need to do a full reset: Turn on the power, set the turn signal to left, turn on the wipers, push the horn button 3 times quickly, press the accelerator once quickly, turn off the power and hold the steering wheel firmly for two minutes. Now turn the power back on, set the turn signal to right, turn on the lights…

      I love fucking with these Americans. What are they going to do? Come after me? They don’t even know where Hyderabad is.”

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