Dala's Leaf buildthread (2015 Nissan Leaf)

Okay so a bit of an update on the PCB manufacturing. As you know a few posts back I posted pictures of a few PCBs that I had ordered. The original idea was to maybe assemble a few CAN-bridges by hand, and then let a local company do the rest. Turns out I have a lot to learn about PCB manufacturing and assembling.

So I visited the only local place in Vaasa that does PCB assembly. Very cool that such a service is available here! Here is the parts picking machine, rolls of components are fed into it, and it places them automatically in the correct location before soldering them into place in an oven.

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The main issue was size. Take alook at these measurements for a capacitor.
0.4mm x 0.2mm x 0x07mm
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- Most of the components are so tiny that you need microscopes to assemble them by hand.
- The PCBs that I order were "Lead Free HASL" coated for the pads. While cheap, this leads to uneven surfaces for the surface mount components. Gold was the de-facto standard for a precision job like this, but I didn't know that :) So new boards will be ordered from an EU supplier. You can learn more about PCB finishes here: https://www.kingsunpcb.com/the-difference-between-gold-plating-and-enig/1604.html
-The edges of the PCB doesn't fit in their clamping machine, so the PCB will be redesigned, extended with a few mm on the sides (only particular to their machinery)

So I'm handing it over to them to fix my mistakes, and I'll learn more how much actually goes into precision automotive grade PCB creation :) I could ramble on more about this, but I'm holding back so we don't get too much offtopic :D
 
So here's something that's good to know when testing used batteries. I recently examined the 40kWh that is soon going into a customer car, and found a small puncture in the top casing. After informing the customer, and then repairing the small puncture, it was time to pressure test the battery.

So a bit about pressure testing. The batteries are by design "waterproof", this specific model can be fully submerged for a few hours without any issues. But they aren't 100% waterproof, some water will get in thru the high voltage harness pins overtime, so it's not possible to store the batteries underwater. So to test the batteries, a pressure tester is needed. There is an official tool, but since it's not possible to buy it I'll have to make my own.

Here is the port on the battery used for testing. It's just a bolt with a copper washer, next to the high voltage connections.

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And here is my improvised tool using some scraps. It's just the same bolt type, with a hole drilled thru it. I put some threads into the bolt head, and attached a hardline pipe and hose to it. It then gets a bike tire pressure valve on the end, which a normal bike pump can be attached to. Tada, 0 testing tool.

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And finally here is the official procedure from the FullServiceManual.

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And yes, the battery passed the test :)
 
So I've noticed that the right hand passenger door makes quite the amount of noise. Any extra squeeks or rattles is extremely noticeable in an electric car, so I need to fix this.

Started with removing the door trim. All you need is a PH2 screwdriver.

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Here is what the sound was like

I fixed it by bending the metal inside the door with my bare hands. That says a lot about the thickness :)
 
Here's something to keep in mind if you're a Nissan Leaf owner. A year ago, July 2019, Nissan issues a service campaign where you could get the battery bonding plates updated for free. Supposedly they would rust heavily and not offer enough electrical conductivity. https://nna.secure.force.com/recall?camp=P9312

The bonding plates, aka grounding straps, are used to securely ground the battery to the chassis. When there is a secure connection it is possible to detect loss of isolation between high voltage positive and negative terminals. If the grounding is flaky, HV could short to chassis GND outside the battery, and the battery LBC could potentially miss this. So it's a very important safety feature.

This weekend I saw the first bonding plate failure on a customer car. Take a look at this!

The mounting bolt was snapped off

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For illustration purposes, here is a grounding strap attached

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I did a complete battery replacement, so got rid of the heavy corrosion that was on the battery. I also replaced the grounding straps with cleaner ones, and made it tip top. In the FSM, it specifies a 0.1 Ohm maximum resistance between chassis and battery, really wish I would have measured that before removing that mess, since it looks like it would have failed that for sure!

All fixed now :)

ginetto said:
FYI a dashboard to monitor your' leaf

https://www.youtube.com/watch?v='-6XHL3zZLUc&feature=youtu.be

with code here:

https://github.com/slim-bean/leafbus

cheers
Click to expand...

Video doesn't work! But looks interesting!
 
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Video doesn't work! But looks interesting!
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fixed in the original post
 
Very cool ginetto!

Tonight I did some more CAN-decoding. The Audio/Video (AV-CAN) is not very well documented on the Leaf. A recent discovery by Jonas Andersson piqued my interest, check this out:


Now to explain more what is happening here. Due to GDPR, the higher spec Nissan LEAF models with the infotainment have a startup nag-screen. This screen has you press ACCEPT to all telemetrics before being able to use the display. By injecting a CAN-message to the AV-CAN, it is possible to bypass this nag-screen and go straight to radio/maps.

So I did what I do, and put the AV-CAN information onto the CAN message database. Anyone wanting to check out more on the AV-CAN, it is now here: https://github.com/dalathegreat/leaf_can_bus_messages/blob/master/AV-CAN.dbc

It is possible to create this as an optional add-on to the CAN-bridges I install, so that it would automatically bypass this screen. I'll have to do some market research to see if it is even wanted :)
 
So I thought this was very interesting. I was tasked with upgrading the battery on a 30kWh Leaf that had 255k km on the clock. That is a lot of km in a very short time. Check out the damage on this Leafspy screenshot

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So as you can see, there is a dip in the graph. This dip is half of the battery, more precisely the rear stack. This is the one that is prone to overheating, and after 3000x fastcharging events (WOW), the rear stack middle cells have taken some extreme capacity loss.

This car was only able to make it 80km before reporting itself as fully empty.

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After putting in a fresher and bigger 40kWh battery, things looked muuuuch better, and the vehicle is ready to cover another 255k km :)

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Very interesting to see that the Leaf otherwise holds up well so many km, it's just the batteries that are the weakpoint.

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Hi Dala, it's been great reading your thread to see what's possible with a bit of ingenuity and know how.

Just wondering whether you've considered or tried installing a Gen3 inverter on a Gen2 Leaf to give it more power? This site suggests the motor is the same, so the newer inverter should give it a decent performance boost, thoughts?


https://www.marklines.com/en/report/rep1899_201907
 
Yes! I really want to do that as soon as I get my hands on an inverter. If it doesn't work due to communication differences, there's always the possibility to modify some CAN messages :)

On another note, I launched a Patreon site last week. I'll be ramping up video productions! Already got the first tech-deep-dive video up on the site. The video will be released to the public in a few weeks, but if you feel like supporting my reverse engineering attempts I wont stop you :)

https://www.patreon.com/dala

The topic for the first video :)
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+1
signed the https://www.patreon.com/dala project as insurance to have long life of my Leaf... and because have to support open initiatives like this one that allow all leaf owner to extent the life of their car. e.g. make it cheaper and less contaminant extending it's life.
 
Thank you so much ginetto :)

And now the video is made available to the public, here's a link if you wanna watch:
 
So here's a fun sideproject! With the help of some friends, we created a working prototype 'nag-deleter' for my friends LEAF, a 2014 24kWH AZE0

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Those of you that have a higher spec LEAF knows how annoying it is to press OK every time you want to use the radio/nav system after starting the vehicle. Due to a recent discovery by one of my Patrons (kudos to Jonas Andersson!), my interest in the quite undocumented AV-CAN grew. Since my own car is a base model LEAF, and I already installed an Android headunit, I couldn't experiment directly with this. Thankfully one of my friends own a LEAF that has the higher spec navigation system, and we could experiment on it.

To bypass the nagscreen is quite easy. Just send some messages onto the AV-CAN (OBD2 pin 11 = H, pin 3 = L) roughly 9 seconds after the car is started. You can get it to go straight to FM, Nav or Status.

To get it to Status, send these 3x messages 100ms between each:

0x681 0x04 30 40 0d b1 ff ff ff

0x681 0x04 40 40 0d b1 ff ff ff

0x681 0x04 50 40 0d 31 ff ff ff

To get it to FM, send these 3x messages 100ms between each :

0x681 0x04 20 40 0d a3 ff ff ff

0x681 0x04 30 40 0d a3 ff ff ff

0x681 0x04 40 40 0d 23 ff ff ff

We then built a ESP32 based box with a MCP2551-IP CAN transceiver tacked onto it. We coded up a simple program that detects when CAN messages start to arrive, waits for X amount of seconds, and fires the desired selection onto the bus. The device is powered via OBD2 pin8, which is a switched 12V supply, so the device doesn't consume power when the car is off.

The finished product, tucked behind the OBD2 port

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Here you can see it in action
 
I did a quick summary on my car as an intro to my channel, it's a bit rough but I'm slowly getting the hand of video editing :D
 
So I recently purchased a row house, that came with a garage and a small storage unit. I started to clean up and paint the garage, along with getting the electrical system up to spec for EV charging. I'm gathering some footage on this, and will make a video on the renovation. But here's a quick before shot on the storage unit, just moved in the printer to it since I needed to ramp up production on 3d-printed parts.


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I already replaced the 60W bulb with a 10W LED to make it a bit brighter. I will remove the improvised bench, and add some insulation to the walls. Then rebuild the bench area. So much FUN! :) I am loving not living in a multistorey building anymore!
 
Congratulation on the purchase of the house. looks like the drywall ceiling is bending and would make a mess if it fell down on top of you or the 3D printer. Really enjoy reading about your projects.

Later floyd
 
Here's a quick video showing where I mount the CAN-bridges when I do battery upgrades on the Nissan Leaf, and also this video contains a quick guide on how to update the software running on these CAN-bridges. The info here is really useful if you are planning to install a DIY CAN-bridge / MITM device on a Leaf!
 
I tweaked my energy subscription slightly.
I used to have a wind-power subscription, which cost 4,90 cent/kWh (+6cent transfer fee). That totals up to 10.9c/kWh. With this subscription, it would cost 4.24 to fill up the car from 0-100% (40kWh).

I scoped the consumption on the new place, it was nice to see data from the few days I've lived here already. This is what it looks like:

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The new agreement I signed is called "climate-electricity", and was 100% renewable energy. Renewable by their definition was solar,wind and nuclear. This I can agree with! I signed up for a lower fee during the night, that way I get 3.60 cent/kWh at night, and 4,24cent/kWh during the day (plus 6c transfer).

Since I normally only charge during the night, it would then cost 3.84 to fill up the car from 0-100%. This is a cost reduction of 10%! I have a hot water heater that runs during the night, so the savings will be even greater over time. Feels good being able to help the power grid and run entirely of renewable!

Now if only I could get some solar panel action going here....
 
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