mr_W
NAXJA Forum User
- Location
- Belgrade, Serbia
Yes, it is blown. Following minor electrical incident in engine compartment, injector #4 wires got melted and there was short.. Which fried output driver inside ECU.
I've disassembled ECU for visual (and infamous electrical burnout odor!) inspection as per instructions from another thread, but didn't find anything obviously wrong. It looks so nice and clean, as it was assembled yesterday!
Anyway, I've checked injector signals with oscilloscope, and it was obvious from result that #4 doesn't get good signal. It is 98% of cycle time 12V and at correct timing it drops to about 7V for some really, really short time. Quite opposite from readings that I get on good outputs for others (short 12V spike, then some small interference and then 0).
So the question for Renix gurus, which of the big ones from ECU - I mean components that are on heatsinks are output drivers? I'm very good with electronics, my welding skills are good and I have great deal on understanding how things with microcontrollers work.. However if anyone knows, it would be much better than removing every transistor and checking it. There are also few IC-s with heatsinks. Hopefully they are not for outputs.. See, the main problem is that I expected to see at least group of 6 of some big elements.. but failed.
Please help, new ECU would be pricey here, and I don't wanna trash this one coz of what looks like trivial problem.
Thanks!
PS, I do have LPG conversion in my XJ, so I can keep driving it.
I've disassembled ECU for visual (and infamous electrical burnout odor!) inspection as per instructions from another thread, but didn't find anything obviously wrong. It looks so nice and clean, as it was assembled yesterday!
Anyway, I've checked injector signals with oscilloscope, and it was obvious from result that #4 doesn't get good signal. It is 98% of cycle time 12V and at correct timing it drops to about 7V for some really, really short time. Quite opposite from readings that I get on good outputs for others (short 12V spike, then some small interference and then 0).
So the question for Renix gurus, which of the big ones from ECU - I mean components that are on heatsinks are output drivers? I'm very good with electronics, my welding skills are good and I have great deal on understanding how things with microcontrollers work.. However if anyone knows, it would be much better than removing every transistor and checking it. There are also few IC-s with heatsinks. Hopefully they are not for outputs.. See, the main problem is that I expected to see at least group of 6 of some big elements.. but failed.
Please help, new ECU would be pricey here, and I don't wanna trash this one coz of what looks like trivial problem.
Thanks!
PS, I do have LPG conversion in my XJ, so I can keep driving it.