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 understanding the position of the gear shifter. It's like when you can't tell if a light switch is on or off.
The P0904 code is triggered when the transmission control module (TCM) detects a problem with the gate select position circuit. This circuit helps the TCM understand which gear the vehicle is in.
The gate select position circuit is responsible for providing the TCM with information about the current gear position. If the circuit malfunctions, the TCM may not be able to correctly identify the gear, leading to potential transmission issues.
• Check Engine Light is on
• Difficulty shifting gears
• Transmission stuck in one gear
• Faulty gate select position sensor
• Damaged wiring or connectors in the circuit
• Malfunctioning transmission control module (TCM)
TCM: Transmission Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the P0904 code.
• Inspect the wiring and connectors related to the gate select position sensor.
• Test the gate select position sensor for proper operation.
• Replace the faulty gate select position sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regular maintenance checks of the transmission system.
• Ensure connectors and wiring are secure and undamaged.
• Avoid aggressive driving habits that can strain the transmission.
Sensor Issue
• Do not ignore the Check Engine Light; address the issue promptly.
• If you experience difficulty in shifting gears, have your vehicle checked by a professional.
• Regularly service your vehicle's transmission to prevent future issues.
Check with your vehicle's manufacturer for specific warranty coverage on transmission components.
The P0904 code has been associated with vehicles that have electronic transmission systems and is more common in models with advanced gear-shifting technology.
Moderate – It is advisable to address this issue soon to avoid potential transmission damage.
Driving with a malfunctioning transmission can be dangerous. Ensure the vehicle is safe to drive before continuing to use it.
• Vehicle at operating temperature
• Transmission in neutral or park
The gate select position sensor is typically located on or near the transmission housing.
Q: Can I drive with a P0904 code?
A: It's not recommended to drive with this code as it can lead to further transmission damage.
Q: How can I clear the P0904 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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