Today’s adventure: the Chevy Bolt gets a double dashcam

Today’s adventure: the Chevy Bolt gets a double dashcam

This turned out really well. You can’t see a single wire anywhere.

Ingredients. 1 generic ‘Car Dash Camera’. Its so generic there is not a model number anywhere on it or the packaging. Nothing. I got it from Aliexpress here. It was described as ”
WiFi Car DVRs Recorder Dash Cam Dual Lens Vehicle Rear Camera Built in GPS Camcorder 4K 2160P Night Vision Dashcam Novatek 96663″. The 4K is a bit of a hmm. It is a pair of 1080P cameras (front, rear). Not exactly 4K, but we’ll go w/ it.

It uses a Sony IMX323 sensor, which is something you need to look for in ‘generic chinese cameras’. You can easily end up with a ‘gopro 4k like’ which sure, it records @ 4K, but the sensor is vaseline and waxed paper, the effective resolution is more like QCIF. But I digress. It has GPS (for speed) and WiFi (so you can install the worlds crappiest app to really do nothing with), and shock-sensor (to lock the recording if you bump). Interestingly it also has a super-capacitor in it for clean power down when you yank the power (and also for parking monitoring… if you are bumped while parked, it will take 60s of capture and snooze again).

Not content with 4G or 5G, they have gone with a 6G lens. Sounds great!

Somehow the 2 x 4MP sensors become 12MP when joined. The marketing specs are… aggressive!

To find out what was inside, first we employed a screwdriver. The only label is T3-NT96663 (Novatek). I’ve attached the datasheet which comes from ip dashcamtalk.Novatek NT96655 Data Sheet

Now, I was wondering, do I wire it to be ‘always on’ or to be ‘Retained Accessory Power’ (e.g. switched). Lets look at the power draw. It seems like its 0.8A @ 5V, so ~4W. Now, you might think, well, the Bolt has a 60KWh battery, run it all the time, how can this matter. But, like all electric cars, there is a small 12V lead-acid battery lurking in there which is used to drive everything except the traction power. Still, that is ~80Ah @ 12V nominal, ~= 960Wh. So at perfect efficiency (hah! physics!) we’d have 240 hours to ‘full flat’, 10 days. Derate by probably 75% (don’t want to run a lead-acid down too far, some innefficiency), we’d be good for a few days. Hmm. I’ll revisit later and put it on a RAP circuit.

Wiring was simple. I considered wiring it into the overhead console power (onstar, dome lights), but instead drove it back to the fuse panel where there were quite a few blanks. I used an ‘add-a-circuit’ micro-fuse tap. I then put it into a small buck converter. The wiring was easy to run (up the kick-panel, up the A-pillar, across the roof) in the lip under the wind-seal. I then wired the rear-camera by wiring from front to rear along the wind-seal and headliner lip. You cannot see the wires at all. The pain bit was getting it through the rubber boots into the hatch-back assembly. For this I used a ‘fish stix’ to fish it. A few stickers, and we are good to go. You can see the fuse panel at the right, lots of empty space to be used (but the add-a-fuse can share an existing tap if needed).

Now on to the app. Oh dear. Rated 1.8 on the Play Store. This will be wonderful. Well, all I can say is, it kind of works if you are patient. ‘Roadcam’ is the name that eventually worked for me, there are a lot, and with such a generic device (no model name at all)…

The user manual… well… it gets the job done. I’m not sure the grammar is world-class, but the concepts come through.

Does it work? Lets see some video (from the rear cam firsts, then the front) for the maiden run:

2 Comments on “Today’s adventure: the Chevy Bolt gets a double dashcam

  1. Hi DB,
    I’ve got a very similar camera from Aliexpress, just the two cameras are hosted together on the one unit body and the label on it is “T3-NT96663-MAIN-V1.-C”.
    Judging from the picture you’ve posted of its internals, it’s the same unit (PCB).

    Now, one huge flaw I found with this DashCam is that its internal battery would not ever have sufficient charge to give us a graceful shutdown when the car A/C power is turned off. Did you find this too?
    I raised this with the seller and never did get a reply. Shortly after, the store when silent. They just left and didn’t even bother closing the store. Just no replies, no products for sale, nothing. I suppose they sold all these cameras with flawed and disappeared.

    Why ‘flawed’ you may ask?
    Well, because when I opened it I found, like yours pictured, that instead of a ‘power-down’ battery it had a supercapacitor instead (blue battery like component). Made of two 2.7V 7Farad capacitors in series. The unit requires 4.6 volts to operate, but this cap quickly falls below 4 volts. Too quick for the unit to complete a shutdown and thus corrupts the two files it was recording when power is lost.

    I’m wondering if you also noticed this, and did you resolve it? On a separate post?
    Super caps are too big to fit something with enough juice in the available space. Not sure if a battery in its place might be a fire risk.
    Thank you.

    • so the camera we have definitely powers down gracefully.
      i put it on the RAP fuse in the chevy, so it stays on for a few min after the car is turned off.
      THen it gracefully shuts down maybe 5s or so after the car removes the retained power. It goes through a chime sequence, a closing animation, and is off.

      we’ve not had trouble with it at all. Been very happy w/ its performance and cheerful 8-bit audio chime as the car is turned on / off.

      i didn’t remove the blue-wrapper, but, it is a supercap, unknown size. I would assume the unit would operate down to about 3V, but didn’t check.

      I can share a higher res photo if it helps, but, i suspect you are right and they are similar PCB etc. Perhaps your `mfg` cheaped out on the supercap?

      –don

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