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 confused about how fast the car's wheels are turning. It's like when a speedometer shows the wrong speed.
The output shaft speed sensor measures how fast the transmission's output shaft is spinning. If the readings from this sensor don't make sense to the car's computer, it triggers this error.
The P1849 code indicates that the transmission control module (TCM) has detected an implausible signal from the output shaft speed sensor. This sensor provides data on the rotational speed of the transmission's output shaft, which is crucial for proper transmission operation and shifting.
• Erratic or harsh shifting
• Transmission slipping
• Check Engine Light illuminated
• Faulty output shaft speed sensor
• Wiring issues such as shorts or open circuits
• Malfunctioning transmission control module
Transmission Control Module (TCM): The electronic component that controls the operation of the transmission.
Output Shaft: The shaft that transmits power from the transmission to the wheels.
• Inspect the wiring and connectors for damage or corrosion.
• Test the output shaft speed sensor for proper operation.
• Check the TCM for any fault codes or malfunctions.
• Replace the output shaft speed sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission maintenance
• Inspect wiring for wear and tear
• Ensure proper sensor installation
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional mechanic.
• Avoid driving at high speeds until the issue is resolved.
Check with the vehicle manufacturer for specific warranty coverage related to the transmission system.
This code is often associated with vehicles that have high mileage or have not had regular transmission maintenance.
Moderate – While the vehicle may still be drivable, ignoring the issue can lead to more severe transmission problems.
Driving with a malfunctioning transmission sensor can lead to unsafe driving conditions. Address the issue promptly.
• Vehicle must be driven at various speeds
• Transmission must be at operating temperature
The output shaft speed sensor is typically located on the transmission housing, near the output shaft.
Q: Can I drive with a P1849 code?
A: It's possible to drive, but it's not recommended as it may cause further damage to the transmission.
Q: How do I know if my output shaft speed sensor is bad?
A: Symptoms include erratic shifting, slipping transmission, and the Check Engine Light being on.
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