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 too high. It's like when you blow too much air into a balloon and it feels like it's going to pop.
The P0843 code is triggered when the Transmission Control Module (TCM) detects a high voltage signal from the transmission fluid pressure sensor/switch A circuit.
The transmission fluid pressure sensor/switch A is responsible for monitoring the hydraulic pressure inside the transmission. The sensor sends a voltage signal to the TCM based on the pressure it detects. If the voltage signal is higher than the expected range, the TCM will set the P0843 code.
• Check Engine Light is on
• Transmission may not shift properly
• Poor fuel economy
• Faulty transmission fluid pressure sensor/switch
• Wiring issues such as shorts or open circuits
• Faulty Transmission Control Module (TCM)
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
Hydraulic Pressure: The force exerted by a fluid within a closed system, such as a transmission.
• Use an OBD-II scanner to verify the code
• Inspect the wiring and connectors for damage
• Test the transmission fluid pressure sensor/switch
• Replace the transmission fluid pressure sensor/switch
• Repair or replace damaged wiring or connectors
• Replace the Transmission Control Module (TCM) if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Honda Accord
• Ford F-150
• Toyota Camry
• Regular transmission fluid changes
• Routine inspection of wiring and connectors
• Avoid harsh driving conditions
Sensor Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving the vehicle aggressively
Check with your vehicle manufacturer for specific warranty coverage on transmission components.
The P0843 code has been commonly reported in vehicles with high mileage or those that have experienced transmission issues in the past.
Moderate – It's important to address this issue to prevent potential transmission damage.
Driving with a faulty transmission can be unsafe and may lead to further damage. It is advisable to have the vehicle inspected and repaired promptly.
• Vehicle must be in park or neutral
• Engine should be at operating temperature
The transmission fluid pressure sensor/switch is typically located on or inside the transmission housing.
Q: Can I drive with a P0843 code?
A: It's not recommended to drive for extended periods with this code, as it could lead to transmission damage.
Q: How can I clear the P0843 code?
A: After repairs, the code can be cleared using an OBD-II scanner. However, if the issue is not resolved, the code will likely return.
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