OBD MPGuino gauge - Page 39 - Fuel Economy, Hypermiling, EcoModding News and Forum

electromike · 05-21-2009, 08:57 PM

I tested it on my car, and the code for the Obduino32K works well. The device will now keep attempting to re-initialize even if it fails the first time. It will try every three seconds or so.

Mart · 05-22-2009, 01:32 PM

Hi,

just put my OBDuino setup (ISO Diagram) under the scope. We've checked at the TX pin of the arduino and the signal respect the ISO9141. BUT at the ISO pin of the mc33290, we've checked and the signal is inverted and do not respect the ISO9141. No surprise why it doesnt work so far.

Obviously, i thought the fastinit KWP2000 style was working but it isnt

.

Anyone have a clue?

Froggy · 05-23-2009, 06:45 PM

I added a slow init and fast init routine for ISO 14230-2, and still no go on the Toyota Matrix.

Nothing was successful.

Mart · 05-23-2009, 09:44 PM

Froggy, a quick test you could do if you have a multimeter avaible: Write a simple loop that drive the TX line HIGH for 5 sec and low for 5 sec. Test at the K-line output of the mc33290 or at the db9 connector. You signal might be reverse for a reason I cant explain right now... mine is like that..

Froggy · 05-24-2009, 10:29 AM

Here's where I am...

When powered by the car, the K line at the car side OBDII plug, I get 12 volts when the Line is HIGH, zero when LOW.

Writting an L or H to the LCD when changing K line outout and writting an l or h to the LCD when reading the K line (after setting the output) verifies the TX/RX functionality is correct on the chip. (this was during a debug test, and not a protocol test).

I've used three protocol inits at 10400 baud with no valid response yet from the car. (it may well be NO response.)

It may need the L line to init (the pin IS present... so it is an option that is open to Toyota to use the line... - though I don't see why they would require it...)

Magister · 05-25-2009, 09:53 AM

I spent countless hours in my Elantra too, with the scope and all, trying to debug it, when I realized it was CAN instead of ISO, even if Hyundai Canada told me "no sir, your car is not CAN"...

Mart · 05-25-2009, 10:03 AM

A good start is finding what protocol your car support

Considering Magister experience, you should rely on multiple sources instead of one

I made the same mistake... and usually dealer dont know much as well...

I'd also advise also building the rs-232 interface located here (prj.perquin.com) and try to run freediag and see if you can connect. It will cut debugging time.... since you will do it from a PC...

anyway so far, (after spending countless hours in my damm car) I have been able to communicate with the denso/subaru ECU using another protocol called SSM (Subaru Select Monitor). It is also way faster than KWP2000 and since it is more a performance oriented application, I think I will explore that route and get back to ISO later down the road.

Mart

Quote:

Originally Posted by Magister

I spent countless hours in my Elantra too, with the scope and all, trying to debug it, when I realized it was CAN instead of ISO, even if Hyundai Canada told me "no sir, your car is not CAN"...

Froggy · 05-25-2009, 07:50 PM

Success!!! (Well not a full success - but OBDuino did communicate.)

Ok, the Toyota Matrix requires the L line to initiate ISO 9141 communications!

Absolutely no communication will proceed without the L line chatter.

I noticed that the K and L lines do exactly the same data routine when using the L, so I simply jumped the two lines.

Plugged the unit in, LCD lit up, and unit failed to init. Turned the key to accessory, and unit connected and the screen when to the PIDs.

Turned the ignition, and data started showing up (gas was being used.)

Now... Turned the ignition off, and the trip data was saved. LCD backlight turned off.

Turn the ignition back on, and LCD backlight did not return on, and data was not updated.

Reset the OBDuino, and everything was then hunky dory....

This is using version 138. I don't know if the failure to resume is the L line, or if there is another defect somewhere. Does anyone else have a problem with reconnection after shutting off the car using 138?

dcb · 05-25-2009, 07:56 PM

Arent you supposed to hold the L-line high after init or something?

Mart · 05-25-2009, 08:00 PM

Nice work.

Mart

Quote:

Originally Posted by Froggy

Success!!! (Well not a full success - but OBDuino did communicate.)

Ok, the Toyota Matrix requires the L line to initiate ISO 9141 communications!

Absolutely no communication will proceed without the L line chatter.

I noticed that the K and L lines do exactly the same data routine when using the L, so I simply jumped the two lines.

Plugged the unit in, LCD lit up, and unit failed to init. Turned the key to accessory, and unit connected and the screen when to the PIDs.

Turned the ignition, and data started showing up (gas was being used.)

Now... Turned the ignition off, and the trip data was saved. LCD backlight turned off.

Turn the ignition back on, and LCD backlight did not return on, and data was not updated.

Reset the OBDuino, and everything was then hunky dory....

This is using version 138. I don't know if the failure to resume is the L line, or if there is another defect somewhere. Does anyone else have a problem with reconnection after shutting off the car using 138?