Years ago I bought one of these little OBD-II wireless diagnostic plugs because I wanted to datalog my car…a hobby project which naturally, like so many of my hobbies, I never finished. The plug has sat in the console of the car, waiting for a day when I needed it. Today was that day. The check engine light came on during a road trip. I haven’t driven a car with a check engine light since I was a kid!
Home late at night, over-caffeinated from the drive, I flashed back to what I’d learned while driving: my plug uses Bluetooth Serial Port Profile (SPP) which doesn’t work with iOS, so I can only use it with Android or Linux. I figured I’d pull out pyOBD which I’d used years ago for my datalogging project as it had some level of GUI, and Claude was confident that it’d get me the diagnostic trouble code that my car wished it could tell me.
I’ve been using AI coding tools so much I decided to roll up my sleeves and get my hands messy. I spent 20 minutes in Python dependency hell all to realize that pyOBD requires Pythons from a more civilized age. I threw my hands up, and wrote a desperate prompt to Claude Code, my own little “Help me Obi Wan Kenobi, you’re my only hope” type prompt that you write when you’re tired. It didn’t bother with pyOBD; it went to python-obd, and just drafted its own little app. I wasn’t looking forward to Bluetooth pairing on Linux and the rfcomm binding dance, but it did some of that work for me.
It’s nothing to write home about, but it’s functional! I had to try it right away. Laptop in the car, ignition on, I dealt with the bluetooth pairing and result:
FOUND 1 TROUBLE CODE(S):
============================================================CODE: P0128
OBD Description: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
I then excitedly pasted the transcript from the application back into Claude Code, which asked me for the make/model of the car, and went on to suggest that I may need a new coolant thermostat (a common problem) and to also check that I’m not low on coolant. It offered to research videos on how to replace, estimated time to repair for someone handy, and estimated shop costs for the job – all the things you’d expect an AI assistant to do.
Makes me wonder – is there a market for a Check Engine AI Assistant App? Buy a plug, skip the stressful “free” trip to the auto shop, get a diagnostic code and an AI recommendation on next steps?
I had this dusty $20 plug in my console for years and AI made it useful in 20 minutes.