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 getting a signal that the pressure in the transmission fluid is lower than it should be. Imagine if you had a garden hose, and there wasn't enough water pressure to water the plants. It's like that, but inside the car.
The P0842 code is triggered when the transmission fluid pressure sensor/switch A sends a low voltage signal to the Powertrain Control Module (PCM), indicating lower than expected pressure.
The transmission fluid pressure sensor/switch A is responsible for monitoring the hydraulic pressure in the transmission. This pressure is crucial for the transmission to shift gears properly. A low circuit signal indicates a possible issue with the sensor, wiring, or actual pressure levels.
• Check Engine Light is on
• Transmission slipping or not shifting properly
• Reduced fuel efficiency
• Faulty transmission fluid pressure sensor/switch
• Low transmission fluid level
• Damaged or corroded wiring or connectors
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
Hydraulic Pressure: The pressure of the fluid within the transmission that helps it operate correctly.
• Check the transmission fluid level and condition.
• Inspect wiring and connectors for damage or corrosion.
• Test the transmission fluid pressure sensor/switch for proper operation.
• Replace the transmission fluid pressure sensor/switch if faulty.
• Repair or replace damaged wiring or connectors.
• Refill or replace transmission fluid if necessary.
• OBD-II scanner
• Multimeter
• Transmission fluid pressure gauge
$100 - $300
Moderate
• Honda Accord
• Ford F-150
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect wiring and connectors for wear and tear.
• Perform routine transmission maintenance.
Sensor Issue
• Do not ignore the Check Engine Light; address the issue promptly.
• Avoid driving long distances until the problem is fixed to prevent further damage.
Check with your vehicle manufacturer or warranty provider for coverage details related to transmission components.
This code has been associated with transmission issues in various models and can indicate a range of underlying problems from simple to complex.
Moderate – While the vehicle may still be drivable, it's important to address the issue soon to avoid further transmission damage.
Driving with a transmission issue can lead to further damage or unsafe driving conditions. Always ensure your vehicle is in good working order.
• Vehicle at normal operating temperature
• Transmission engaged in drive or reverse
The transmission fluid pressure sensor/switch is typically located on the transmission housing or near the valve body.
Q: Can I drive with a P0842 code?
A: It's not recommended to drive with this code active, as it could lead to further transmission damage.
Q: How do I reset the P0842 code?
A: After fixing the issue, you can reset the code using an OBD-II scanner. However, if the problem isn't resolved, the code will likely return.
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