Technical Description of OBD-II Trouble Code
The voltage circuit for the Turbocharger/Supercharger Boost Control B Supply is too low.
What does that mean?
This is a generic diagnostic trouble code (DTC) for powertrain issues and is commonly found in OBD-II vehicles. This code can apply to various vehicle brands such as Chevy (Chevrolet), GMC (Duramax), Dodge, Ram (Cummins), Isuzu, Ford, Vauxhall, VW, and others. The specific repair steps may vary depending on the year, make, model, and powertrain configuration of the vehicle.
Turbochargers, superchargers, and other forced induction systems use energy from the engine (such as exhaust pulses or belt-driven screw-type mechanisms) to increase the amount of air entering the combustion chamber, resulting in improved volumetric efficiency.
In forced induction systems, the intake pressures need to be adjustable to meet the power requirements of the operator. Manufacturers use a boost control valve (also known as a waste-gate, boost control solenoid, etc.) that is monitored and controlled by the Engine Control Module (ECM) to maintain the ideal air/fuel mixture. The boost control valve adjusts the vanes in the charger to regulate the amount of boost (intake pressure) in the chamber. A problem with the boost control component can cause drivability issues. When the ECM loses control of the boost, the vehicle may go into “limp” mode to prevent engine damage from over/under-boost conditions, which can result in a potentially damaging rich or lean air/fuel mixture.
The letter “B” in this code may refer to a connector, wire, circuit group, or other component. The manufacturer’s specifications are the best resource for determining the specific meaning of “B” in this context.
The ECM triggers the check engine light (CEL) and displays the P005E code when it detects a fault in the boost control system.
The P005E DTC is activated when the ECM detects a lower than desired electrical value in the boost control supply voltage circuit labeled as “B”.
A turbocharger and related components:
What is the severity of this DTC?
The severity is considered moderate-high. A problem in the forced induction system can alter the air/fuel ratio, potentially causing significant engine damage if left unaddressed. In addition to the risk of damaging internal engine components, the vehicle’s fuel efficiency will also be negatively affected. Therefore, it is strongly recommended to repair any faults in the forced induction system.
What are some of the symptoms of the code?
Symptoms of a P005E trouble code may include:
What are some of the common causes of the code?
Possible causes for the P005E code include:
What are some P005E troubleshooting steps?
Basic Step #1
It is important to note that forced induction systems generate a significant amount of heat, which can cause severe burns if the engine is cool and proper protection is not used. Visually locate the boost control solenoid, which is typically mounted directly to the charger. Ensure that its mechanical functionality is in good condition.
This step is crucial because the solenoid controls the charger and boost pressures. If you can manually move the lever from the solenoid to the charger housing, it indicates that the solenoid is functioning properly. However, in some systems, manual movement may not be possible.
Basic Step #2
In some cases, the solenoids may have adjustable levers that help find the optimal position. However, this varies significantly between manufacturers, so it is important to research the specific details for your vehicle.
NOTE: Be cautious and avoid causing damage to expensive charger components during this step.
Basic Step #3
Depending on your specific setup, the module may be mounted directly to the boost control as an assembly. Check for any signs of water intrusion. If there is any corrosion, water damage, or other signs of damage, the assembly (or just the module, if possible) will likely need to be replaced.
Basic Step #4
Pay close attention to the harnesses connected to the boost control solenoid. These harnesses are exposed to high levels of heat. If there is any heat damage, it will likely be evident early in the troubleshooting process.
