Diagnostic Help
What does that fault code actually mean?
Search by fault code or describe what you're looking for. Try a code such as P0299, or terms like underboost, DPF, fuel pressure or camshaft.
Understand the code
Find out what the code actually describes rather than jumping straight to a replacement part.
Know what to test
Work through sensible diagnostic checks and understand the reasoning behind them.
Learn from real faults
Find related Speed Tweaks videos, case studies and workshop examples as the library grows.
Fault Code Library
Browse diagnostic guides
Real diagnostic information, workshop examples and sensible test routines. The library will continue to grow as more Speed Tweaks guides are added.
8 fault codes available
P0299
Turbocharger / Supercharger Underboost Condition
The ECU isn't seeing the boost pressure it expects.
P0343
Camshaft Position Sensor "A" Circuit High — Bank 1 / Single Sensor
The ECU is seeing a camshaft-position signal or circuit condition that is higher than expected.
P2293
Fuel Pressure Regulator 2 Performance
The ECU has detected that the high-pressure fuel system is not achieving or controlling fuel pressure as expected.
P2453
Diesel Particulate Filter Pressure Sensor A Circuit Range/Performance
The DPF pressure signal isn't behaving as the ECU expects.
P2463
Diesel Particulate Filter Restriction — Soot Accumulation
The ECU has determined that soot loading or restriction in the DPF has become excessive.
P246B
Vehicle Conditions Incorrect for Diesel Particulate Filter Regeneration
The vehicle is not meeting one or more of the conditions required for DPF regeneration.
P2520
Fuel Pressure Fault — Volvo Application
On some Volvo applications, P2520 can be presented as a fuel-pressure related fault.
P2633
Charge Air System Offset Drift Under Engine Load — Mercedes CDI
The Mercedes engine-management system has detected a discrepancy in the charge-air system under load.