Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer noticed a problem with the part that controls how much air goes into the engine on one side of the engine. It's like one side wants to open the door more than the other side.
The code indicates a mismatch between the desired and actual throttle position values on Bank 2 of the engine.
The throttle actuator is responsible for controlling the amount of air entering the engine. On Bank 2, the system has detected that the desired throttle position value does not match the actual position. This can be due to a malfunction in the throttle actuator, wiring issues, or a problem with the engine control module (ECM).
• Check Engine Light illuminated
• Reduced engine performance
• Poor throttle response
• Faulty throttle actuator
• Wiring issues in the throttle actuator circuit
• Faulty engine control module (ECM)
Throttle Actuator: A component that controls the opening and closing of the throttle valve.
Bank 2: The side of the engine opposite Bank 1, typically where cylinder 2 is located.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the throttle actuator for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the throttle actuator if faulty.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• BMW 3 Series
• Audi A6
• Mercedes-Benz C-Class
• Regular maintenance checks
• Keep throttle body clean
• Ensure proper electrical connections
Engine Performance
• Avoid driving aggressively until repaired.
• Get the vehicle inspected by a professional.
Check with your vehicle manufacturer for warranty coverage on the throttle actuator.
This code has been more commonly reported in vehicles with electronic throttle control systems.
Moderate – Should be addressed soon to avoid further engine performance issues.
Driving with a malfunctioning throttle actuator can lead to reduced engine performance and may affect vehicle safety.
• Engine running
• Vehicle in park or neutral
The throttle actuator is located on the intake manifold of the engine, typically on Bank 2, which is the side of the engine with cylinder 2.
Q: Can I drive with a P155C code?
A: It's not recommended to drive for long periods with this code as it can affect engine performance.
Q: How do I clear a P155C code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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