P262B
Control Module Power Off Timer Performance
The internal power-down timer of the engine controller does not run as expected. The module either stays awake too long after key-off (battery drain) or shuts down too early (no aftertreatment cool-down or learn-write).
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Intermittent main relay opens earlyPossible
- Software timer counter corruptedPossible
Parts involved
- Control Module
- Main Relay
P262B is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.