My daily pearl white

[bzh kevin]

Hi everyone!

I bought my s15 last august and haven't been very active on the forum so I think it's now time for me to introduce myself and the car properly .

I am Kevin, 29 years old and French (nobody is perfect) . I have owned a couple of 200sx's in the past, an s13 and an s14 and really liked them . I then had a few different cars after them but the thought of getting an s15 never really left the back of my mind .
I like cars in general but i have a soft spot for all the 90's Japanese sport cars . I guess wasting a lot of my teenage years on gran turismo have something to do with it .

I also own a couple of other cars . Here is my track prepared RX7 :




And here is my R32GTR :




As much as I love the two cars above they are not the best for everyday use . I needed something reliable and cheap-ish to run everyday . I decided to give the S15 a go as my s14 was really good as a daily and I assumed the S15 would be the same, so far I haven't been disappointed .
I got it imported by torque GT last summer . Really easy company to deal with and the car was exactly as they described it when I picked it up .
It's a pearl white spec-R with aerokit . Everything is stock (I have fitted a set of 350z rays at some point but it rubbed the arches on bumpy roads, I stuck the factory ones back on .)
I am not planning to do anything to the car apart from keeping it clean and maybe a set of wheels later and also replacing the Japanese head-unit that doesn't work too well .

 

[bzh kevin]

My headlights started to become opaque . A bit of sanding and polishing brought them back to life .

before:



after :

 

[bzh kevin]

Last weekend I took the car around Bedford autodrome .

The car is still completely stock . It is a lot fun but the factory brake setup gets overwhelmed pretty quickly .





Unfortunately by mid afternoon one of the turbo water line split nearly all the way around and I dropped a good amount of coolant that resulted in the engine overheating quite badly .

The car is off to the garage to get the turbo coolant line changed and make sure the headgasket didn't get damaged .

 

[bzh kevin]

I haven't posted anything to this thread in a long time . The car is still stock and running well . I booked a drift day in Santa pod earlier this week .
Couldn't commit to the faster part of the track as I was a bit worried about damaging the car.

 

[Joeh]

That standing water

impressive driving! I can see why you can’t commit to that high speed section... CONCRETE WALL!!

 

[bzh kevin]

I finally took the decision to get rid of the head unit that came with the car from Japan and replace it with something useful .
I am terrible at looking at my gauges/dashboard when running on track so I decided to have a bit of fun and design a system that can display custom gauges and set alarms when things turn bad (so I can avoid the situation I was in a couple of post above!).

First thing was to get rid of the head unit . Of course I was met with the classic spaghetti wiring that seem to come with every car from this era .



After an hour trying to make sense of where they all run I managed to get everything cleaned up.



There is still a fair bit of wires running under the carpet to the DVD player and audio filters running at the back . It was getting quite dark outside so I stopped there but hopefully this will be a straight forward job once I have a bit of light .

I am in no way a coding expert but I like doing a programming as a hobby so I decided that it would be a good challenge to stream data directly from the ECU .

I found some good info on how to build DIY NISSAN consult interface here : https://www.plmsdevelopments.com
I also found some old code from someone that did his own system a while back (https://github.com/fridlington/K11Consult) . I thought about trying to reuse it but I was written in an old version of python and I figured out that I would probably be better of to just writing everything from scratch .

I already had a USB to Nissan consult port :



I believe it is also possible to use some serial to USB converter that are much cheaper but don't quote me on this .

Connecting and pulling data from the ECU was surprisingly straight forward . As a proof of concept and a bit of a joke I made a custom gauge using a photo of a work colleague .

View attachment gauge_blur.mp4
















In the future I would also like the possibility to read and erase fault codes .


The next step will be to run the code on a raspberry pi and a 7" touch screen .
I had a quick look and the screen won't fit the console without either cutting the console trim or building a bezel around the screen to recess it a bit .
I like the idea of a bezel as it would also give me some space to fit a couple of USB ports which could be used to play music from a memory stick and also plug a keyboard to update the program without having to take anything apart .

 

[bzh kevin]

I did a bit of work on the design of the gauges .
I want something easy to read and OEM looking(-ish) . Although I don't mind flashy gauges in race car like interior I am not a huge fan of them in a stock looking ones.

After experimenting with various design I settled with this one :



The idea would be to just turn the lettering red and sound an alarm when one of the parameter goes over a certain limit to let me know that something isn't right .

I will probably also need to make a slightly darker version for night driving .

 

[bzh kevin]

A bit more done today . I finished pulling all the remaining wires from under the carpet .

The software side is giving me a bit of a hard time as I use an old game engine to handle the display and it is proving to be not as straight forward as I was expecting .

After a couple of hours battling with my code I decided to take a break and start working on a set of 3D printed brackets to hold the screen in place . They are screwed directly on the OEM head unit brackets/frame .


I also gave up on the idea of building a bezel around the screen and decided to simply use a USB extension that will hidden in the ashtray or the console storage instead .

 

[Cess]

Unbelievable stuff Kevin. Absolutely love what you are doing.

Reminds me of a recent episode of Car SOS where they build a custom LCD dash for a 1980 Esprit which is completely OEM looking. And, in a similar vein, the recent MightyCarMods, where they get a plug and play LCD dash for the Exige.

I think it would be such a trick and modernising touch for the S15

 

[bzh kevin]

Thanks !

I haven't seen the Car SOS episode . I will try to see if I can find it when I have 5 minutes .

I did watch the MightyCarMods one . The Lotus dash is really cool . I just assumed it just came from the V6 exige but after doing a quick resaerch it looks like they don't come with a digital dash from factory . I am not sure if lotus developed it themselves or repackaged a TOYOTA dash but it is pretty awesome that they still offer upgrades for 15+ years old models .

I test fitted the screen in the car this morning . As usual I couldn't measure anything properly to save my life .
The screen needs to move a couple of mm back (inside the car) and a bit lower to be over flush for the HVAC controller unit .

 

[bzh kevin]

After printing another set of brackets the screen now fits .



Things are getting there on the software side too . Most of the display/UI is working . It is only running on my laptop at the moment and read values on a simulated ECU that generate random values . The next step will be to run the software with the real ECU .

View attachment gauge WIP.mp4

 

[bzh kevin]

I tested the code on the raspberry pi . I was a bit shocked it worked straight away with the touch screen . I am not used to my program working first try .
Next I need to make sure I can get a stable 5v power supply in the car with a little delay after the car is turned off to let the raspberry pi to shut down safely .
View attachment gauge touchscreen.mp4

 

[Cess]

That's very, very impressive. What all parameters can you display on screen?

 

[bzh kevin]

I choose to limit what I can display to :
- air flow meter voltage
- battery voltage
- coolant temp
- injector duty (calculated from injection time and RPM)
- lambda sensor voltage
- oil pressure (not available from the ECU but can be taken from the oil pressure switch)
- ignition timing
- RPM
- throttle position

In theory it is possible to have access to more data as listed in this document (in the data name section) : Nissan consult sensor table

I have been working on reading fault codes today but it is a bit harder to check how well it works as my car runs well at the moment . So far I have been able to send a request for fault codes to the ECU and get a message back . The issue I have is that the value of the message I get back is 85 which doesn't seem to be a valid fault code (I was expecting 55 which means there is no issue) .

 

[bzh kevin]

I turns out the fault code list I was using was incomplete . I found a better one in the forum's technical section : S15 fault codes (looking there from the start would have been a good idea).

Fault 85 is listed as 'VTC Solenoid Valve Circuit ' . I find it strange as there is really no symptoms or anything that would indicate something is wrong .
I think I will add the 'clear fault codes' functionality to my program and see if the fault code comes back .

 

[bzh kevin]

A bit more done today .
The good news is fault codes can be read, displayed on screen and cleared.

The not so good news (but not that bad) is that I am getting a bit confused with how to translate the reply from the ECU when querying for fault codes.
The communication with the ECU is done via hexadecimal characters .
You send a series of specific hexadecimal characters to the ECU to let him know what data you want (specific sensor value, fault codes...) and then it send back another series of hexadecimal characters .
The first few characters let you know how long the message is and where the values of interest start in this message .
Once you get rid of these starting characters the message for fault code reading is structured like this :
fault 1 - number of starts since last recorded - fault 2 - number of starts since last recorded - fault 3 - number of starts since last recorded ....and so on

I am unsure is if the hexadecimal characters need to be translated or not.
I assumed they needed to be translated into decimal (basically normal numbers ) as it worked fine when reading sensor values .
Now where it is really confusing is that the hexadecimal character 55 correspond to 85 in decimal . which is why it displays a fault 85.
Code 55 means that there is no malfunction with the car which would make sense since my car works fine.

I think I will have to force the car to throw a different fault code just to double check how the message from the ECU should be interpreted . hopefully unplugging the MAF sensor will do the job .

 

[bzh kevin]

Tonight I sorted out the power supply .
It is basically a voltage regulator with a few extra things around .
A microcontroller (arduino) and a relay to keep the power on for a few seconds after the car is turned off so the raspberry pi has time to shutdown properly .
It also allows to monitor if the lights are ON or OFF so the screen brightness can be modified accordingly .

 

[bzh kevin]

Now in the car and running but for some reason the sensor reading freezes after reading fault codes . It is probably a simple error .
The power supply is pretty sketchy as well so more work is needed on that as well . Slowly getting there though .

View attachment gauge_s15.mp4

 

[sx-si]

very impressive work, looks like you can add many sensors to the rasberry pi for more info

 

[hugh janus]

this is very cool