[rtware923]

A few months ago I picked up a generic ELM327 OBDII scanner. I used it on my dad's truck around a month ago and it read the code fine. Today (nothing wrong with my 2017 Mazda 3) I plugged it into my car to just get it set up incase I ever needed it and some weird things happened.

First, the car wouldnt start with the scanner plugged in.
Second, after abandoning my mission of using it, a check engine light was on my dash.

Has this happened to anyone else before? Any insight?

I will be taking it to the dealership this coming week but would rather fix it on my own if it is something simple. (dealer is an hour away)

 

[bsliv]

I bought a couple of ultra cheap (<$5) scanners. One was dead on arrival. The other worked for a few days on my 2015 3i. I was driving around with it connected and then all the idiot lights came on. I immediately pulled over and shut it off. Restarted and the lights went away. Took it to the dealer and explained what happened. The service department wrote on their form that the obdii port was tampered with but caused no damage.

Since then, I bought an OBDLink MX scanner. I leave it connected 24 hrs a day for the past couple of years. No issues with it.

Not exactly your situation but thought I'd share anyway.

 

[rtware923]

Update: Check engine light went off when I left work today. OBD2 reader is now in the trash.

 

[catnapped]

I bought a couple of ultra cheap (<$5) scanners. One was dead on arrival. The other worked for a few days on my 2015 3i. I was driving around with it connected and then all the idiot lights came on. I immediately pulled over and shut it off. Restarted and the lights went away. Took it to the dealer and explained what happened. The service department wrote on their form that the obdii port was tampered with but caused no damage.

Since then, I bought an OBDLink MX scanner. I leave it connected 24 hrs a day for the past couple of years. No issues with it.

Not exactly your situation but thought I'd share anyway.

Agreed...spend the extra $ and get something like that. Can pull a lot more information from one of those than the cheapy $10 ones that may break something.