JDM engine diagnostic tool?

I am doing a gen 4 swap on my ST165. I had my harness done by wiregap. He added an OBD2 connector. I guess Japan has their own version of OBD2? Can anyone suggest a scanner with code reading and live data capability? Are there any Android Bluetooth interfaces?
 

Andy

Member
Their ODB2 should comply, or it's not ODB2. Have Autozone hook up to and do a diagnosis to confirm....

Get an ELM327 device from EBay (about $25), it will plug into the ODB2 port and make the data available through Bluetooth.

Get the "Torque" application ($5) for an Android phone.
https://torque-bhp.com/wiki/Main_Page

With Torque, you will be able to:
- check engine codes, while driving...
- create custom gauge displays
- Superimpose gauges, and a map overlay on a video of the road your're driving...
https://www.youtube.com/watch?v=J4gPCwSPPSQ
- + more

Andy
 

underscore

Well-known member
^ order it from dx.com for $5 and it'll come with a copy of Torque. The best feature to me is the ability to set warnings with the gauges, so you get a heads up if you begin to overheat or lose oil pressure etc etc.
 

FC Zach

Active member
Is there a dumbed down written how-to that shows step-by-step instructions on attaching an OBDII port to a pre 96 that even a layman like myself :) could be confident in doing? I've been wanting to attach one of these bluetooth adapters for years now but I am not a software engineer/programmer so a lot of what I have read from others makes zero sense. . . :shrug:

I've meet Andy a couple times (smart guy) and the arduino gauge project as well as OBDII scanner really fascinated me (he is a software and/or electrical engineer/programmer). He tried explaining it all to me but after 550 miles of driving and sleep deprivation, there was no way I was retaining much of what was said on top of stripping his parts car of much needed goodies. . . and even then, there was more faith in my ability than there should have been.

I'm sure it's not difficult and I'm most likely confusing this simple task with an arduino project he had mentioned but I'd still like to see a cut-and-dry explanation.
 

Andy

Member
Thanks Zack,

There are two components key components, the hardware and the software.

Hardware:
- 12 voltage regulator
- an Arduino
- blue tooth module
- 5.1 volt zenier diodes


The voltage regulator simply limits the power supply voltage into the Arduino at 12v. The Arduino is the computer making the computations.
The Bluetooth module provides the pathway to get the data to your phone/tablet. The 5.1v zenier diodes are used limit (cap) the voltages from the igniter (rpm feed) and/or a injector feed.

Voltages being read by the Arduino "must" be in a 0-5v range. The key ECU measurements, MAF, TPS, Vac/Boost pressure are already done at a 0-5 volt signal range. Thus, they can be monitor directly by the Analog to Digital input ports.

The igniter and fuel injector are "pulses", not a signal defined by a "changing" voltage. Once the Zenier diode has reduced the voltage to 5v it can be feed into one of the digital inputs which can detect interrupts. An interrupt occurs when the voltage "state" changes. There are four states: low (0v), rising (0-5v), high(5v), and falling (5v-0). The interrupt is then used time the pulses. For RPMs an interrupt is used to count one of the four states (Revolutions), divide by time, yields RPM. With the fuel injectors the 'rising' (injector open) and 'faling" (injector closed) states are used to calculate the injectors open time. Knowing the injectors open time with and injectors flow rate and some math will show "load" based on fuel consumption.

In my first pass at this I used the Fuel Injector pulses to calculate the RPMs. But it did not always work. Reason: when you let off the gas and the cars momentum is spinning the engine, you don't need fuel.

The Wiring Harness... unfortunately, you have to at least "touch it". But, you do not need to "cut it". I tapped into my wires a couple inches from the ECU. I did NOT cut any wires. I did: carefully remove some insulation, solder on a signal wire, and replace the insulation with liquid tape and electrical tape. Also, I used a old PC serial cable for the 'signal/power' wire to the Arduino. This was done to allow it to be easily removed from the car.

Software:
It was some time ago that I wrote the software. At hat time I did quite a bit of research to ensure it had not already been done.
What I did find was the MPGuino project, a project to calculate realtime MPGs, which helped with the fuel injectors. But it had nothing about bluetooth, ODB2, etc....

I researched the ODB2 protocol and then wrote the code to provide the data stream accordingly through the bluetooth device. I haven't looked at the code in years, thus don't want to dive into it at the moment...

If anyone wants a copy I can dig it out and email a copy. You will need to install the Arduino code compiler onto your PC to compile and upload the compiled code to the Arduino.

Oh, it was not a "simple" task there were no "how to's" when I put this together. There are a ton of them on this topic now. Buying an ELM327 and plugging it in, that was simple.

Hope this helps.

Andy
 

FC Zach

Active member
Eh, it helped me remember that it is not simple or plug-and-play and that it is definitely easier said than done. What little I thought I remembered, I thought the use of an Arduino was for your repurposed clock and that adapting an OBD port was just wire connections but it is far from that simple.

Thank you for clearing all that up for me. In most cases I like to jokingly say that "I'm too stupid to know I can't do it" but in this case, this is beyond my expertise and I am wise enough to not attempt something I know nothing about and potentially turn a project into a disaster. . . better left for the professionals. So till the day comes that there is a "kit" (or whatever), I'll just leave it be :)

Thanks again
 

Andy

Member
Here is another video, a close up of the Arduino (from March 15, 2012).
https://www.youtube.com/watch?v=iCBArP-C9Xc

I did forget a couple items on the hardware... some resistors, LEDs, and a prototype board...
If you can follow a simple schematic and solder the hardware is not to bad.
The software is already done, that was the tricky part and where the time was spent....

If there is interest I might be convinced to dig back into it and do a DIY write up on it, which would include:
Parts and schematic, the software and how to upload it into the Arduino (not that hard), info where and how it might be customized, also testing to confirm all is working as it should, no shorts, etc...

That needs to be a dedicated thread... (starting to feel like I'm thread jacking...)

Andy
 

FC Zach

Active member
Andy":28ky43w2 said:
Here is another video, a close up of the Arduino (from March 15, 2012).
https://www.youtube.com/watch?v=iCBArP-C9Xc

I did forget a couple items on the hardware... some resistors, LEDs, and a prototype board...
If you can follow a simple schematic and solder the hardware is not to bad.
The software is already done, that was the tricky part and where the time was spent....

If there is interest I might be convinced to dig back into it and do a DIY write up on it, which would include:
Parts and schematic, the software and how to upload it into the Arduino (not that hard), info where and how it might be customized, also testing to confirm all is working as it should, no shorts, etc...

That needs to be a dedicated thread... (starting to feel like I'm thread jacking...)

Andy

I can follow schematics I guess, but if the diagram looks anything like this. . I"M OUT :nono:
33065870800_246cea2f72_z.jpg


I'd be interested but like I mentioned earlier, I know my limitations and I'm sure this is above my paygrade :)

underscore":28ky43w2 said:
If you want to hook up to an older Toyota, check out the ToyOBD1 tool: http://jfbreton.blogspot.ca/2014/02/toy ... gines.html

He responds pretty quickly on FB as well: https://www.facebook.com/groups/1505898572959292/

Thanks, I'll check this out. I don't see USDM 92-93 3s-gte on the compatible list. .

PS, sorry for threadjacking in case this isn't pertinent to the OP
 
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