So I got a VAG COM KKL adapter to try and use with RomRaider and I never could get it to work (trying to find the culprit of a p0420 code, see pg. 144-145 of P0420 Diagnosis) and so I ordered another cable thinking I got a bad cable but it still didn't work. Then I was looking in the service manual I have (got it off ebay a while back, don't know how legit it is) and following its procedure, with the ignition on (engine off) pin 7 is reading 9.1V which according to this is bad.
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Looking at the cable, looks like pin 7 and 8 were shorted (which looks like that is needed on some other vehicles after a quick google search). I removed the short, so it's just pin 7 connected to pin 7 but no luck. Pin 8 appears to be the ignition switched power, so it goes up to 12V when the ignition is on and I think that may have shorted something out somewhere.
It looks like the k-line goes to a number of different places. I am guessing the problem might be with the ECM and something shorted to 9V on there but I suppose it could be on any of them.
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Any thoughts on the best approach? Do the electronics use the k-line to communicate with each other or just with the external device?
I am thinking maybe the best approach would be to try and remove the k-line pins at each of those connectors (starting with the easiest to get to) and see if the voltages drops (to 0V? or just below 5V?).
Another option would be to try and take out the ECM and look at it (which I am guessing is where the problem is). I am an electrical engineer (work on avionics) but it is a little scary to take out the ECM and poke around.
Anyone have any other thoughts?
The CAN works just fine as my OBDLink MX+ still works.
Thanks.
Looking at the cable, looks like pin 7 and 8 were shorted (which looks like that is needed on some other vehicles after a quick google search). I removed the short, so it's just pin 7 connected to pin 7 but no luck. Pin 8 appears to be the ignition switched power, so it goes up to 12V when the ignition is on and I think that may have shorted something out somewhere.
It looks like the k-line goes to a number of different places. I am guessing the problem might be with the ECM and something shorted to 9V on there but I suppose it could be on any of them.
Any thoughts on the best approach? Do the electronics use the k-line to communicate with each other or just with the external device?
I am thinking maybe the best approach would be to try and remove the k-line pins at each of those connectors (starting with the easiest to get to) and see if the voltages drops (to 0V? or just below 5V?).
Another option would be to try and take out the ECM and look at it (which I am guessing is where the problem is). I am an electrical engineer (work on avionics) but it is a little scary to take out the ECM and poke around.
Anyone have any other thoughts?
The CAN works just fine as my OBDLink MX+ still works.
Thanks.
