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 a part in the car that helps change gears is stuck and not moving like it should.
The transmission uses solenoids to control the flow of fluid, which helps change gears. If one of these solenoids is stuck, it can cause problems with shifting.
The P1806 code indicates that the transmission control module (TCM) has detected that one of the shift solenoids, either 'A' or 'B', is not operating correctly due to being mechanically stuck. This can prevent the transmission from shifting gears properly.
• Transmission not shifting properly
• Check Engine Light illuminated
• Vehicle stuck in one gear
• Dirty or contaminated transmission fluid
• Faulty shift solenoid
• Wiring issues or poor electrical connections
Shift Solenoid: An electromechanical device that controls the flow of transmission fluid in an automatic transmission.
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
• Check the transmission fluid level and condition
• Inspect the wiring and connectors to the shift solenoids
• Test the shift solenoids for proper operation
• Replace the faulty shift solenoid
• Clean or replace the transmission fluid
• Repair or replace damaged wiring or connectors
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Ford Focus
• Mazda 6
• Nissan Altima
• Regularly change transmission fluid
• Perform routine transmission maintenance
• Inspect wiring and connectors periodically
Transmission Issue
• Avoid driving the vehicle until repaired to prevent further damage
• Consult a professional mechanic for diagnosis and repair
Check your vehicle's powertrain warranty for coverage on transmission components.
This code is common in vehicles with high mileage or those that have not had regular transmission maintenance.
High – Address this issue promptly to avoid transmission damage.
Driving with a malfunctioning transmission can be unsafe and may lead to further vehicle damage.
• Vehicle should be at operating temperature
• Perform tests with the vehicle in a safe, controlled environment
The shift solenoids are located inside the transmission, accessible by removing the transmission pan.
Q: Can I drive with a P1806 code?
A: It's not recommended to drive with this code as it can lead to further transmission damage.
Q: How do I reset the P1806 code?
A: After repairs, use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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