I'm interested in deriving the OBD codes what software or commands will I use?

same question! what would be the software???

hey man, how can I build to work with my PWM protocol Ford 2000 car? Its the same thing?

For PWM you need an ELM327 interfaced with it

I assembled my elm327. but i dont understand because there is a diagram to ISO and another to CAN protocol. I need to buy the MC33290 chip? the PWM is converted in CAN protocol?.....sorry, but i am lost now....thanks...

error in a link must be

Hi,

Do i need an ELM 327 to make an interface only for CAN protocol, or with the MCP2551 and the MCP2515 it's enough??

This ISO protocol works with my VW passat with KW1281 protocol? Or I need something more?

The TX/RX of the mc33290 works like rs-232 ??? what is the right sequence to interface the ISO protocol? There is any table of codes??

I want to take a plunge into this project. Any tips on procuring the items listed...Please give your thoughts. Also, I do not have an electronics kit yet any suggestions on where to get a good kit.

I can't seem to find the MC33290 anywhere. The Freescale page says the IC is now out of production, are there any alternatives (excluding the ELM327)? Thanks!

As with the guy above, does anyone know where to get the MC33290 or perhaps has one spare they could send me (id be willing to pay for postage/item)

i think you could buy them in alibaba.com for for 5 USD each, but u gotta order at least 10 ea plus the shipping cost...

HI bros, i got a ELM327 to USB interface alrdy , and if a wanna connect the interface with a arduino board(with LCD screen) , what else i have to do after i wire pin 16 of the ELM327 to pin 1 (TX) of the Arduino and pin 17 of the ELM327 to pin 0 (RX) of the Arduino? Thx a lot!!!!

Kan

WiFi? OBD II Function similar to the ELM327,This OBD II WiFi? Code Reader is specially designed to work with all OBD II compliant vehicles. It is required by EPA that All 1996 and newer vehicles (cars and light trucks) sold in the United States must be OBD II compliant and this includes all Domestic, Asian and European vehicles.http://www.eobdii.com/wifi-obd-ii-car-diagnostics.html

For ISO9141 protocol instead of MC33290 you can use Si9243AEY. It works(verified).

I am currently trying with MCP2515. In the code, there doesn't seem to be an option for this. I assume it just works?

The code dedicates the int0 vector to the button press status PINC, yet in the first schematic int0/int1 aren't hooked up, and in the second schematic, they are connected to the 2515 and LCD. Something seems very wrong here.

Peter, Take a look at the MPGuino code - you might find the answer there (I think the Interrupts were taken there for Injector / VSS pulses).

If you can't get the MC33290, I can verify that the ISO9141 interface works with a Vishay Si9241A (K-Line only) chip on my 1998 Subaru Legacy L. (The Si9243 chip mentioned by darius above includes a driver for the K-line and the L-line as well, which I didn't need.) I managed to solder jumper wires to the pins and breadboard it. For now I just have the CS pin tied to my TX pin and it works great. I was able to get the chip at Digi-Key for a couple of bucks plus shipping - about $5.00 total. I'm using a bare ATMega328P on a breadboard with a 16 MHz ceramic resonator. I thought it wasn't working for a while - then realized that even though I had 12V at the OBDII connector from the car with the car off, the ECU is not powered up and capable of responding until I turn the ignition key(!) I kinda hurt myself slapping my forehead after that, but I'm very happy to have it working now.

Hi Jpcuzzo, did you make any changes to the connections between the Si9241A and the DB9M as well as ATMega328P as illustrated in the schematic diagram of the OBDuinoInterface page(other than tying CS\ with TX)?

I received the Si9241A a few days ago but so far, have not had any success in communicating with the ECU. However, I am testing with the ECUSIM 2000 (a ECU simulator) I bought from a scan tool vendor.

Appreciate any inputs/advice. Thank you.

Hey there, I'm about to try this project out on a 1996 Honda civic. I fill be using the Freescale MC33660EF for my ISO interface, since the original MC33290 is no longer available. I'm just wondering though about the 510 ohm resistor that is included in the interface circuit beteen pins 4 and 1 on the frescale ic. What specifically does that do, is it just a pullup on the car's dataline? how critical is the 510 ohm value? Looking at the datasheet i found a line that states RISO = 510 Ω to VBB, CISO = 10 nF to Ground. Does this mean that i need to add a capacitor between the bus and ground aswell?

Thanks -Julian

Julian, I'm interested in the same thing you are. The new data sheet seems to provide a little more clarification of the 510 ohm resistor, but I lack the technical background to understand why that is. Seems there's a lot of other components, such as diodes, that are not used in the OBDuino schematic. Hmmm.

Andrew, After hunting through my misc parts i couldn't find any 510 ohm resistors, so i have some on order. Freescale sent me a couple of the MC33660EF chips for free as samples, so once i get the resistors, i'm going to wire it all up as shown on the schematic above and see what happens. It is my belief at the moment, that most of the diodes and other components should be built into the car on the ECU side of the K line. I'll report back as to whether or not it works with my Honda.