Quote:
Originally Posted by turbo_c Aren't we all fed up of being scared out of our pants when that dreaded "check engine" light comes on in the dash?
Aren't we fed up of being taken for a ride by the auth. service guys with their 1Lakh + devices that tell us to replace the most expensive parts on our MPFI engines?
If only we could talk to the ECU directly, huh?
Well... I dont think we need lots of money to talk to 'em:
I heard that most mordern ECUs have a simple Serial Interface. If this is true, then we should be able to hook it up to one of the COM ports on a PC and use "Hyperterminal" to talk to the ECU !
Making sense of the gibberish it would put out would be the next step. For this we would need to write software that will decode the byte stream; given the protocol.
I'm a computer geek and can do whatever it takes once I have the byte stream on the PC... I'm looking for some help from other computer / electronics / automobile geeks on Team BHP...
Here's what I need at this point:
1. Do all ECUs have a serial interface? If not, electronics guys / gals; let me know what needs to be done to get the data into a Serial / Parallel / USB port on a PC.
2. I would need the protocols to write the software. Is there a "Standard ECU protocol"?
3. 'Erm, not trying to sound dumb, but... where exactly is the ECU located ? - Different cars = Different places I suspect... (I own an MPFI Esteem)
Looking forward to lots of chatter on this thread.
- T u r b o C - |
reading the output from the ECU can be done, there are lookup tables available which tell which code corresponds to which parameter of which sensor, each manufacturers list can be obtained, but then what we get is read only mode.
Im not sure if we can at this level try to mod the chip, modding of chip will require a different technology altogether .. the EEPROM cant be programmed with a mixture of our "after market code tuner " code and the original OEM code... we may have to write another set of instructions and fit another chip altogether...
Our Indian cars are ISO ObdII protocol compliant atleast the Baleno and the Lancer .. we can use a VB.net application to read the data, I had started this project on my own but the cost of simulator cards was prohibitive.... bcoz u cant just plug into an ecu from the 1st day. U need to debug with the simulator card with varying parameters ...and once it is stable then connect to the ECU. there is a russian company which makes these and having dealers in US.. but the total cost of the harness+OBd2 adapter+ r32 to USB + simulator brings the price so high that it is not worth experimenting with and in the end what u get is a readonly software with some bugs the same software can be bought off the shelf for a very less amount. I spoke to some mechanic/tuner guys near LA and Pasadena about this .. but the repsonse which i get is "dude dont mess with the ECU" .. I think we should leave the ""rechipping"" to the big boyz like Innovate,Greddy and Vishnu etc etc. these guys have dedicated cars like mobile test labs with high end sensors which they use to play around with.. we cant experiment with 1 car without all the sensors and test equipment, and biggest adavantage they have is that they may have some knowledge of OEM EEPROM ..but they wont let us know !!
if u want to try some coding.. u try coding for a software which displays the data from ECU in real time becoz its "doable" but expensive.
any suggestions guys .. ?
Last edited by Rehaan : 22nd July 2008 at 13:11.
Reason: inappropriate language
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