P1129 — Ford — Downstream Heated Oxygen Sensor Signals Reversed

P1129 (Ford): Downstream Heated Oxygen Sensor Signals Reversed — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Downstream Heated Oxygen Sensor Signals Reversed. Source catalogue definition; confirm applicability using vehicle service information.

Affected system: Powertrain