Where does AI get its information?
Chatbots such as ChatGPT, Gemini and Claude learn from huge amounts of public text: owners' forums, repair articles, videos and general technical material. That gives them a good general understanding of how car systems work and which faults are common.
What they don't have is your car. They can't measure anything, they can't see the wiring, and they usually don't have the manufacturer's current wiring diagrams or technical bulletins for your exact model and year. They work from your description and from what is statistically likely.
That makes AI a good explainer and a poor tester.
What AI can and can't do
Where AI helps
- Explaining what a warning light or fault code means in plain English
- Giving you an idea of whether the car is safe to keep driving
- Talking you through simple jobs such as bulbs, fuses or a battery change
- Helping you describe the symptoms clearly before you ring a garage
- Making sense of a quote or a repair you've been told you need
Where it runs out
- Faults that come and go, or only appear when hot, cold, wet or over bumps
- Wiring, earth and connector problems, which have to be found by testing
- Battery drains and communication faults between control modules
- Exact pin numbers, wire colours and values for your specific model
- Module programming, key programming and coding, which need the right equipment
A fault code isn't a diagnosis
This is the point most often missed. A fault code tells you which circuit the car noticed a problem on. It doesn't tell you why.
Take a code that names a sensor. AI will usually suggest replacing that sensor, because that is the most common fix across thousands of cars. But the same code can be set by a broken wire, a corroded connector, a poor earth, a blown fuse or a fault in the control module. If the sensor wasn't the cause, a new one changes nothing and the money is gone.
Proper diagnosis means testing. We measure voltages under load, check signals on an oscilloscope, test the wiring between components, and confirm the cause before any part is replaced.
Already asked AI? Bring it with you
We're happy to hear what you've found out. It often saves time. The most useful things to tell us are: