Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the electrical line that helps control the engine's throttle on one side of the engine. It's like a wire that isn't working right, so the car can't control how much air goes into the engine properly.
The throttle valve enable line circuit is responsible for sending signals to control the throttle valve's position. A low signal indicates a possible wiring issue or a problem with the throttle actuator.
P157D is triggered when the powertrain control module (PCM) detects a low voltage condition in the throttle valve enable line circuit for Bank 2. This could be due to a short circuit, open circuit, or a malfunctioning throttle actuator.
• Check Engine Light is on
• Reduced engine performance
• Poor throttle response
• Faulty throttle actuator
• Wiring issues such as short circuits or open circuits
• Faulty PCM
Throttle Valve: A component that controls the amount of air entering the engine.
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
• 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 PCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $600
Moderate
• Audi A4
• Volkswagen Passat
• BMW 3 Series
• Regularly inspect and maintain wiring harnesses.
• Keep electronic components clean and dry.
• Schedule regular vehicle diagnostics.
Sensor Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for a thorough inspection.
Check with your vehicle manufacturer for warranty coverage on electronic components.
This code has been associated with throttle control issues in vehicles with electronic throttle bodies.
Moderate – Addressing this issue promptly can prevent further engine performance problems.
Driving with a malfunctioning throttle system can be unsafe and may lead to unexpected engine behavior.
• Engine running
• Throttle actuator engaged
The throttle actuator is typically located on the intake manifold near the throttle body.
Q: Can I drive with a P157D code?
A: It's not recommended to drive with this code as it can affect engine performance and safety.
Q: What happens if I ignore the P157D code?
A: Ignoring the code can lead to poor engine performance and potentially more costly repairs.
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