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 pressure of the fluid in the transmission. It's like if you had a water balloon and couldn't tell if it was full or not.
The P0841 code is triggered when the transmission control module (TCM) detects a problem with the transmission fluid pressure sensor or switch A circuit's performance or range.
The transmission fluid pressure sensor/switch A is used by the TCM to monitor the hydraulic pressure in the transmission. If the sensor readings are outside the expected range, the TCM may not be able to control the transmission properly, leading to this error code.
• Check Engine Light illuminated
• Erratic or harsh shifting
• Transmission slipping
• Faulty transmission fluid pressure sensor
• Damaged or corroded wiring or connectors
• Low transmission fluid level
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
Hydraulic Pressure: The pressure of fluid within the transmission system that helps control gear shifts.
• Check the transmission fluid level and condition.
• Inspect the wiring and connectors for damage or corrosion.
• Test the transmission fluid pressure sensor for proper operation.
• Replace the transmission fluid pressure sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Refill or replace transmission fluid if low or contaminated.
• OBD-II scanner
• Multimeter
• Transmission fluid pressure gauge
$150 - $400
Moderate
• Honda Accord
• Nissan Altima
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect wiring and connectors during routine maintenance.
• Use the correct type of transmission fluid.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle excessively until repaired.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been commonly associated with sensor failures and wiring issues in vehicles with automatic transmissions.
Moderate – While the vehicle may still be drivable, it can lead to more severe transmission issues if not addressed.
Ignoring this code can lead to transmission damage, which may result in unsafe driving conditions.
• Vehicle at operating temperature
• Engine running and transmission engaged
The transmission fluid pressure sensor is typically located on the transmission housing.
Q: Can I drive with a P0841 code?
A: It's possible, but not recommended as it can cause further transmission damage.
Q: How do I reset the P0841 code?
A: Fix the underlying issue, then use an OBD-II scanner to clear the code.
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