Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is saying that the part that controls how much air goes into the engine on one side isn't working right.
This code indicates that the throttle actuator, which controls the airflow to the engine, is not providing the expected feedback or position data on Bank 2.
The throttle actuator is responsible for regulating the amount of air entering the engine. Bank 2 refers to the side of the engine opposite Bank 1 in a V-type engine. The Engine Control Module (ECM) monitors the position of the throttle actuator and expects certain values. If the actual position value deviates from the expected value, this code is triggered.
• Check Engine Light is on
• Poor engine performance
• Reduced fuel efficiency
• Faulty throttle actuator
• Wiring issues or poor connections
• Faulty ECM
Throttle Actuator: A device that controls the amount of air entering the engine.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle actuator and related wiring for damage or disconnection.
• Test the throttle actuator for proper operation.
• Replace the throttle actuator if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdrivers and wrenches
$200 - $800
Moderate
• BMW 5 Series
• Audi A6
• Mercedes-Benz E-Class
• Regular maintenance and inspections
• Keep throttle body clean
• Ensure proper electrical connections
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you notice performance issues.
Check with your vehicle manufacturer for specific warranty coverage on throttle components.
This code has been associated with throttle actuator issues in various V-type engines, particularly in European vehicles.
Moderate – Addressing this issue promptly can prevent further engine performance problems.
Driving with a malfunctioning throttle actuator can lead to unsafe driving conditions due to reduced engine performance.
• Engine at operating temperature
• Vehicle in park or neutral
The throttle actuator is usually located on the intake manifold on the engine, specifically on Bank 2 for this code.
Q: What does Bank 2 mean?
A: In a V-type engine, Bank 2 refers to the side of the engine opposite Bank 1.
Q: Can I drive with a P155D code?
A: It's not recommended as it can lead to poor engine performance and potentially unsafe driving conditions.
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