OBD2 connection failure

[ric342]

Hello, reaching out hoping for some guidance on how to proceed. Back story, I bought a 2013 Frs with a known bad head gasket. When purchasing the vehicle I went to get the codes and had issues with the obd2 port, I just chalked it up to being the cheap scanner. I got it home and continued to have issues with the obd2 connector. If I held it in the right spot it would have power but move it and it would reset.
I thought it was a simple bent pin or connector issue, so I bought a new obd2 connector and wired it up.

Now we have constant power from the obd2 but the same communication error. Whether it’s a cheap Matco scanner or a launch unit the same communication issue persists. I took a look at the obd2 port on my other Frs and the wires match up, so it’s not a wiring issue from the obd2. I started to think that it was an issue with the aftermarket alarm system so I removed it and started the car and got the same result.

Side note, when the car is in the run position with the scanner connected the car will not start. When I remove the scanner and take the key out then try again the car starts up. I’m leaning to a bad computer but have never experienced anything like this, what are your thoughts??

I called the dealer to price out an ECM and they said it doesn’t come programmed and would need the car there to program the new computer. Is there a way to have them just flash the new ECM so that I don’t have to take it to them??

[finch1750]

Try an extension. The 2013 OBD ports tend to get kinda shitty. I couldn't pass smog because they couldn't get a good connection on my OBD and it threw hella CELs each time, but the extension fixed it since there is less movement in the connection.

I have used this one for 3 years now and it's worked good so far.

https://www.amazon.com/dp/B09GBGNC87...d_asin_title_1

[ric342]

Originally Posted by finch1750

Try an extension. The 2013 OBD ports tend to get kinda shitty. I couldn't pass smog because they couldn't get a good connection on my OBD and it threw hella CELs each time, but the extension fixed it since there is less movement in the connection.

I have used this one for 3 years now and it's worked good so far.

https://www.amazon.com/dp/B09GBGNC87...d_asin_title_1

Ill give it a try and update you.

[ric342]

Originally Posted by finch1750

Try an extension. The 2013 OBD ports tend to get kinda shitty. I couldn't pass smog because they couldn't get a good connection on my OBD and it threw hella CELs each time, but the extension fixed it since there is less movement in the connection.

I have used this one for 3 years now and it's worked good so far.

https://www.amazon.com/dp/B09GBGNC87...d_asin_title_1

Tried it and got no change.
I checked for signal from the can bus high and low speed. Im reading 0 ohms and have disconnected each of the modules one at a time to see whats causing the short to ground and have yet to turn up anything. I,m grasping at straws here and the dash is torn appart, any help would be amazing!