What a car says about itself
Telemetry, diagnostics and the numbers under the bonnet, minus the marketing. Explanations you can take to the workshop.
- 5 min read
From a code to a decision: how CarStream explains fault codes
A fault code answers none of the three questions an owner has: can I keep driving, what is it likely to be, what do I check first. What the Explain button sends, what comes back, and why the answer is shaped the way it is.
- 5 min read
What a fault code actually tells you, and what it doesn't
P0420 is not a diagnosis. It is the engine computer saying that one measured value stayed out of bounds long enough to matter. How to read that, and why clearing it fixes nothing.