jonand 0 Posted May 21, 2006 My Mi still wont start, and I am wondering if anyone has the logic/flow diagrams or an understanding of the ecu operation. I would expect that the ecu receives its signal from the CAS sensor to tell it that the engine is turning - this would then allow the pump relay wire 20c to be earthed via pin 20 (the pump relay would have been energised previously at ignition ON via the injection relay). At this time I would also expect ecu pin 1 to transmit a signal to the ignition module to commence triggering the coil. My problem is that the pump relay is not being earthed through the ecu - hence no fuel (runs fine if earthed directly) AND I have no spark at all. My initial diagnosis was a CAS fault - but I have tried another one to no avail (apparently these sensors cannot be tested reliably without an oscilloscope). I am now thinking ecu fault unless my understanding is incorrect. Any thoughts would be gratefully received (or anyone with a good 4.1 for sale ) Regards Jon Share this post Link to post Share on other sites
the_mighty_one 0 Posted May 22, 2006 hey, it does sound like an ECU fault from what you describe, however have you checked that the earth and feed wires [constant, ignition etc] are all present and working? do you have an ECU fault light wired up? does the illuminate when you first turn on the ignition? if it doesnt it suggests the ecu is either not powered up or is not earthed correctly? Share this post Link to post Share on other sites
jonand 0 Posted May 22, 2006 hey, it does sound like an ECU fault from what you describe, however have you checked that the earth and feed wires [constant, ignition etc] are all present and working? do you have an ECU fault light wired up? does the illuminate when you first turn on the ignition? if it doesnt it suggests the ecu is either not powered up or is not earthed correctly? Hi, Will check again tonight - does the ecu casing need to be earthed as well as the relevant pins ? I am looking into the fault light system and have just ordered a code reader as it happens. Thanks Jon Share this post Link to post Share on other sites
Fuqa 0 Posted May 22, 2006 Hi, Will check again tonight - does the ecu casing need to be earthed as well as the relevant pins ? I am looking into the fault light system and have just ordered a code reader as it happens. Thanks Jon i can probably provide u with ecu pin out data if u require it Share this post Link to post Share on other sites
jonand 0 Posted May 22, 2006 i can probably provide u with ecu pin out data if u require it Hi Fuqa, I have some basic pin out data (descriptions) but no values. If you have better information that would be most useful. I see that you are in the neighbourhood - you dont happen to have a spare motronic 4.1 burning a hole in your pocket do you ? or the facility to link mine into a running Mi16 ? Thanks for your help anyway. Jon Share this post Link to post Share on other sites
Fuqa 0 Posted May 22, 2006 Hi Fuqa, I have some basic pin out data (descriptions) but no values. If you have better information that would be most useful. I see that you are in the neighbourhood - you dont happen to have a spare motronic 4.1 burning a hole in your pocket do you ? or the facility to link mine into a running Mi16 ? Thanks for your help anyway. Jon ive just got all the info off autodata for you now. all values included. yup im in milton keynes to but dont have an ecu unfortunately. :-( u got a fax local to u? if so pm the number and fax over this data to u cheers Rich Share this post Link to post Share on other sites
jonand 0 Posted May 22, 2006 ive just got all the info off autodata for you now. all values included. yup im in milton keynes to but dont have an ecu unfortunately. :-( u got a fax local to u? if so pm the number and fax over this data to u cheers Rich Thanks Rich that would be most useful - will PM you now Regards Jon Share this post Link to post Share on other sites
KRISKARRERA 2 1 Cars Posted May 24, 2006 have just ordered a code reader as it happens.No need for a silly expensive fault code reader. I did mine with a piece of wire and counting the flashes of the "k" light. Share this post Link to post Share on other sites
jonand 0 Posted May 24, 2006 No need for a silly expensive fault code reader. I did mine with a piece of wire and counting the flashes of the "k" light. Thanks for that. I haven't got the k light wired in atm (race car - no dash) - and just bought a code reader from fleabay for not a lot of money. Regards Jon Share this post Link to post Share on other sites
