A code that is active, stored or pending
Three words next to the code. They decide whether to go to a garage today or simply keep an eye on it.
Next to the code the app writes one of three words. The difference between them matters more than the difference between the codes themselves.
Active
The unit sees the fault right now. The check is failing at this very moment and the lamp is usually on.
This is the state you deal with today. If the code is about misfires and the lamp is blinking, you should not drive at all.
Stored
The fault happened, but it is not present now. The unit wrote the code and keeps it in memory until it is satisfied the trouble does not repeat — usually forty warm-up cycles, after which the code clears itself.
A stored code is not «already fixed». It is «the condition is not met right now». P0128 may not appear at all in summer and come back with the same code in autumn.
Pending
The unit noticed something once and is waiting for confirmation. Many checks require two consecutive matches before lighting the lamp: that filters out one-offs — a bad tank of fuel, a momentary sensor glitch.
This is the most valuable of the three states. The lamp is not on yet and the trouble is already visible — it can be caught before it becomes active.
How to use this
A pending code appeared and vanished — most likely a one-off. Note it down and carry on.
A pending code repeats — the fault is real, just rare so far. Look at the freeze frame: under what conditions it happens.
Stored with the lamp off — the most common state on a used car. Check the readiness monitors: if they are not complete, the codes were cleared recently.
Active — read the code and decide today.
When buying a car
The seller says «no faults». Ask about pending ones: they get cleared less often, because people do not know about them. And compare with the readiness monitors.
