turbo2ltr

Kevin, what year is the ECU you are looking at? Sig, What year is the ECU I have? (88?) The circuit I have is vastly different. Pin 21 goes to a 100k to ground, also through a 4.7 k, to the E or C of what is probably a transistor.. it says M317Z...didnt find it after a quick search. (I'm a little reluctant to dissassemble Sigs ECU to see if its NPN or PNP). What I also found is that transistor's base goes to the C(E) of another transistor whos E© goes to a 5V pullup and the base goes to the output of an opamp through a 4.7k. Perfect setup to drive the line. But the kicker is this. Â The Original pin, after it goes through the first 4.7k (also has a .47uf to ground) goes to another 4.7k and to the input of an A/D converter. (Pin 3 of a Toshiba TC35095P) Still sure it's not going to work? Regards, Mike Montalvo digital tuning, inc. www.pocketlogger.com

Would you buy a $3500 socket set before you knew for sure that you were going to be a mechanic? It's a rather large investment to make when the return on it is not really known. Kevin seems to have already tried the MUTT and knows it doesn't work so our method for retrieving data won't work. Since we aren't really interested in making an external A/D box, it doesn't seem like there is much we can do. Regards, Mike Montalvo digital tuning, inc. www.pocketlogger.com

Very well. I guess theres no point in getting a MUTT. Sorry guys. Sig, Give me your address so I can send you're stuff back. Regards, Mike Montalvo digital tuning, inc. www.pocketlogger.com PS: The DSM service manual also only shows a single transistor driving the line that does the 1 wire protocol...

DSMs only use one pin. That doesn't mean they can only check error codes. They use a one wire protocol. You also can check error codes on DSMs with that same pin. This is why I want a MUTT. I am aware of current micros with A/Ds. But then you need filtering, switching, level conversion, etc, hardware too. It adds up. Why would you want to spend the money when the ECU has all that built in already? Regards, Mike Montalvo digital tuning, inc. www.pocketlogger.com

It doesn't sound like the TCL-1 is what I need if it only reads codes. Our interest is reading the various engine sensors *through* the ECU. The idea is to use the exisiting diagnostic interface to get this information, not something similar to a "breakout box" as that requires external Analog to digital converters (Expensive). If the MUTT can display more than error codes, then we can reverse engineer the protocol and duplicate it on the Palm. But we need a MUTT to do it... Regards, Mike Montalvo digital tuning, inc. www.pocketlogger.com