Error Code P0048: What It Means & What To Do?

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If you are experiencing lack of engine performance, with increased emissions and sounds from the engine and first indication being the Check Engine Light On, then there might be some problem with the turbocharger or air intake systems and components, leading to P0048 error being stored in the PCM.

OBD code P0048 means that the ECU (Engine Control Unit) has detected an out of range reading of too high operation in the turbocharger or supercharger boost control solenoid circuit. This might also be physical damaged turbochargers and failed sensors along with problems with the wiring and connectors connecting the sensors circuits.

This code is related to the electrical circuit A as an area of the boost solenoid system circuit.

• What causes problem of Turbo/Super Charger Boost Control Solenoid Circuit High?
• Boost pressure sensor faulty
• Turbocharger boost control solenoid is defective
• Damaged wiring in the boost control solenoid circuit
• Electrical wiring/connectors in the boost sensor 5-volt reference circuit is loose, corroded, burnt, or disconnected
• Failure in Turbocharger

1. Turbocharger - Examine the turbocharger for physical damages due to varying temperatures and air pressures over time and replace if damaged.
2. Supercharger - it is an important component to maintain proper fuel to air ratios and thus, if damaged, needs to be replaced immediately.
3. Diagnostic Tools - Use Professional diagnostic tools for correction of the OBD error code which is detected. Buy pro grade tools now.
4. Engine Control Unit - The ECU can also be faulty, and can lead to having wrong information being transmitted further. Thus, replace if found faulty.
5. Boost Control Solenoid - If the solenoid does not function properly, then the air pressure will not increase and affect the performance of the engine. Replace it now!
6. Boost Control Sensor - A faulty boost control sensor can lead to improper mixture of air and fuel as it will not be able to correctly know the air pressure, thus causing performance failures. Buy new sensors form us now!
7. Electrical Connectors - Always check for corroded, opened or shorted wiring and connectors while diagnosing this error and replace them immediately.

In addition to service/check engine soon lamp illumination, code P0048 may lead to the following symptoms:

Common Symptoms

• Lack of engine performance
• Abnormal hissing noises from the engine.
• Engine and transmission temperatures increase
• Black smoke from the exhaust
• Fouled spark plugs
• Cylinder detonation
• Engine acceleration reduced

The P0048 code means that the boost is too high, or the output voltage to the ECU is too high.

• Check to see if the boost pressure is in range and operating smoothly. The boost pressure sensor is very important to the fuel management system to control the quantity of fuel. Thus, perform this step carefully.
• Check for sensors and wirings that have been damaged over time and need replacements. Always use assistance of a skilled mechanic.

P0048 is properly diagnosed with an advanced scan tool capable of factory sensor readings (not just one from an auto parts store). A qualified technician can read the data from the advanced scan tool to determine when the problem occurred, or if it is still occurring. They may clear the code/light and test drive the vehicle while monitoring the scan tool data to see if the fault returns or is present.

Based upon the conditions of the test, possibly clearing the code, and road testing the car while monitoring the data, further diagnosis may be required. Diagnosis may require multiple tools such as:

• A technician typically begins by hooking the vehicle up to an OBD-II scanner in order to verify that the code is present, and check for other codes.
• This data along with freeze frame data is recorded, and the codes are then cleared to see if they reoccur.
• Next, there should be a visual inspection of the wiring and connectors to check for loose connections, corrosion, or shorts.
• A specialized tool may be used to test the boost control sensor. Other tests of the sensor and circuit components may help pinpoint the problem, as well as inspection of the connectors and manifolds.
• If there is a physical problem with the turbocharger, this could cause the air pressure to go off far enough to trigger a code P0048.

Common mistakes when diagnosing the P0048 Code

Do not replace components without carefully inspecting the problems. Be sure to clear the turbocharger oiling system which otherwise leads to turbo failure related to the bearings on the turbocharger shaft. Replacing the turbocharger without complete testing of the bypass valve or wastegate function and electrical circuitry is also the cause of wrong diagnosis.