[BimmerNugget]

I have a 2011 Bmw 328i AT sedan. The car is 100% fine except 1 little issue...

The car does not recognize any OBD2 scanners at all!!

I used a $180 Innova OBD2 Scanner that I use for my Toyotas and Hondas, when I plug it into the BMW obd2 port, all I get is a code U0100. "Lost communication with ECM/PCM A".

NOW HERE IS THE WEIRD PART....

1) A quick google search tells me that a code U0100 is pretty serious, however my car drives 100% smooth and starts up every single goddamn time! My car has no lights and no issues whatsoever.

2) My car just passed New York State safety and emissions inspection. They plugged their emissions inspection computer into my OBD2 port and I passed emissions. If my OBD2 port was busted, how can they connect to my car computer??


***I was about to buy a Bavarian Technic scanner to test my waterpump flow rate soon, but I'm afraid it won't work since there is something up with my OBD2 port?

Can someone help figure out what the heck is going on??

[BimmerNugget]

BimmerGeeks

I only tried my own scanner, but I pulled up to Autozone to use theirs and it was the same problem.

My scanner works 100% fine on my Toyota Sienna and Honda CRV. So my scanner is not the problem.

[BimmerNugget]

BimmerGeeks

I checked all OBD2 related fuses already, no problems.

The weirdest thing about all this is how the heck did I pass New York State emissions testing, they test emissions by plugging into OBD2 port.

[BimmerNugget]

BimmerGeeks

Yes, I had the issue before the emissions test. I thought for sure I was going to fail NYS emissions testing, but I passed it. So that made me even more confused.

[gbalthrop]

The pin sockets in the OBD port can get damaged. On my 2007 N52KP the following pins are active (you can see the metal sockets in the 16 hole plastic port) and the pin#s are in VEERY small numerals on the outboard edges of the port:

Pins functional: 1, 4, 5, 7, 9, 16
1: ignition switched 12V+ (signals tool that ignition is on)
4: Chassis ground
5: Signal ground
7: K-Line
9: Tachometer/RPM signal
16: battery voltage, 12V+ (unswitched?)
Fuse#2: 5Amp, protects OBD circuit

I would start with a visual inspection of the port, identify metal sockets, and test for 12V+ battery power @ pin 16 and make sure pin 1 is ignition switched 12V+

Perhaps someone can suggest a safe way to test K-line?

George

[BimmerNugget]

Sorry, I really have no clue how to test the OBD2 port pins. I just did a visual inspection of the pins and there is no rust or bent pins.

The previous owner that I bought my car from is pretty clueless about the car as well. she had the battery replaced about 1 month before I bought the car. Could the U0100 code be related to improper battery registration?

She also said she has attempted to jumpstart the car before she gave up and bought a new battery. IS it possible she fried some electronics while trying to jumpstart?