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 is having trouble reading the speed of the part that helps the car move forward. It's like if your bike's speedometer wasn't working right.
The P1811 code indicates that the input or turbine shaft speed sensor is sending a signal that is lower than expected to the vehicle's computer.
The input/turbine shaft speed sensor measures the rotational speed of the transmission's input shaft. The sensor sends this data to the Powertrain Control Module (PCM), which uses it to control transmission shifting. A 'circuit low' code means the sensor's signal is below the expected range, possibly due to a wiring issue, sensor failure, or PCM problem.
• Check Engine Light is on
• Transmission shifting problems
• Poor acceleration
• Faulty input/turbine shaft speed sensor
• Wiring issues such as shorts or open circuits
• Faulty Powertrain Control Module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the input/turbine shaft speed sensor for proper operation.
• Replace the input/turbine shaft speed sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Malibu
• Pontiac Grand Prix
• Buick Regal
• Regularly inspect and maintain transmission components.
• Ensure wiring and connectors are secure and undamaged.
• Perform routine diagnostic scans.
Sensor Issue
• Avoid driving at high speeds until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
Check your vehicle's warranty for coverage on transmission components.
This code is commonly associated with GM vehicles and often relates to sensor or wiring issues.
Moderate – Should be addressed soon to prevent potential transmission damage.
Ignoring this code could lead to transmission failure, which might be dangerous while driving.
• Vehicle at operating temperature
• Transmission in drive mode
The input/turbine shaft speed sensor is typically located on the transmission housing.
Q: Can I drive with a P1811 code?
A: It's not recommended to drive for long periods with this code, as it can lead to transmission issues.
Q: How do I reset the P1811 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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