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P0103 & P0113 - Ground Wire Issue Looking for Feedback
I have a 2010 Nissan Altima 2.5. Last post I made was about my throttle body connector having an open and required extreme pressure to make a connection with TB attached or not.
During that troubleshooting I am assuming I brought to a light an unknown issue. KOEO with MAF unplugged I get an immediate P0113 about IAT circuit being high. It's a six wire connector with only five wires connected laid out as following:
1 - Blank
2 - 12V
3 - Ground to ECM
4 - Signal
5 - IAT 5v
6 - Ground to ECM
Pins three and six share the same ground wire that goes to the ECM. I tested the continuity from the MAF harness down to the ECM harness and for the most part it existed every time. Occasionally, it would drop out and then I plugged my MAF in, I would get the P0103 and I would see 8v on both ground wires at my meter and 5v on scan data. I could do a bypass test on the signal wire and see the changes in my scan data, so I know my computer was working. I then checked the pins again at the ECM harness and it seems like the pin from the ECM into the harness might not have a very tight connection. I have very thin probes I was testing how the resistance felt between some other pins and this pin. I also noticed sometimes I didn't have continuity unless I wiggled my probe around in the pin hole (if that makes sense).
It works now, but I am a little confused why I would have 8v show up the ground wires? Unless, the slight loose pin hole is not the issue and it's possible I have short to ground that I haven't noticed?
It works now, but I am a little confused why I would have 8v show up the ground wires? Unless, the slight loose pin hole is not the issue and it's possible I have short to ground that I haven't noticed?
Sounds like the ground was either open or high resistance because of the pin issue at ECM. When you see voltage like that on a ground wire it ain't grounded. Why 8V instead of B+ could be due to the electronics inside MAF or because the ground was high resistance rather than fully open??
