What does this code mean?
The monitored boost is insufficient for the calibrated operating condition. This describes a control result, not proof of a failed turbocharger. Air-path restriction, control-system behavior and environmental conditions must be evaluated within the vehicle procedure. The cited GM bulletin documents an ice-related case with possible reduced power.
Sources and interpretation [1] [3]
A code identifies a detected condition, not a part that must automatically be replaced.
Before replacing a part
Record whether the fault occurs only in cold weather and compare desired with actual boost. Review the exact engine's air path and boost-control tests. A cold-weather bulletin is not evidence that every P0299 requires a turbocharger or software replacement.
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P0299-00Turbocharger UnderboostP0299Turbocharger UnderboostManufacturer communications
2Original wording in English
RAM
Reported code forms P0299
Cylinder Head Replacement This bulletin involves replacing the cylinder head. During a previous repair an incorrect cylinder head was installed.Customers may experience a Malfunction Indicator Lamp (MIL) illumination.…
RAM
Reported code forms P0299-00
Flash: 3.0L Diagnostic And System Improvements This bulletin involves reprogramming the Engine Control Module (ECM) with the latest available software. A small number of customers may experience a Malfunction Indicator…
Check vehicle applicability
1A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Ram | PROMASTER | 2014 |
Sources and interpretation
These explanations are editorial summaries of the linked manufacturer material. PDF page numbers count from the first file page. Original publications are in English; translations are reference aids. A cited edition is not a claim that it is the manufacturer's latest instruction.
- Audi TT Quick Reference Specification Book · October 2013 ↗
Audi of America · PDF page(s) 137 ·
- 22-NA-002 · P0299/P0234 during cold or freezing temperatures ↗
General Motors · PDF page(s) 1 ·
- 2024–2025 MY OBD System Operation Summary for Gasoline Engines ↗
Ford Motor Company · PDF page(s) 86, 87 ·
Source check date · 2026-10-27
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.