Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that a part in the car that helps change gears isn't working well. It's like when you try to change gears on a bicycle, and it doesn't shift smoothly.
The code indicates that the pressure control solenoid 'D' is not allowing the transmission to shift properly due to low pressure.
The pressure control solenoid 'D' is responsible for regulating hydraulic pressure in the transmission to ensure smooth shifting between gears. When the solenoid fails to maintain adequate pressure, it results in poor shift performance.
• Harsh or delayed shifting
• Transmission slipping
• Check Engine Light is on
• Faulty pressure control solenoid 'D'
• Transmission fluid leak
• Blocked hydraulic passages
Solenoid: An electromechanical device that controls fluid flow in the transmission.
Hydraulic Pressure: The pressure of fluid in the transmission that helps change gears.
• Check for transmission fluid leaks
• Inspect and test the pressure control solenoid 'D'
• Perform a transmission fluid pressure test
• Replace the faulty pressure control solenoid
• Repair any transmission fluid leaks
• Flush and replace transmission fluid
• OBD-II scanner
• Transmission fluid pressure gauge
• Basic hand tools
$200 - $500
Moderate
• Ford Focus
• Mazda 3
• Chevrolet Malibu
• Regularly check and maintain transmission fluid levels
• Perform scheduled transmission service
• Avoid aggressive driving habits
Transmission Performance Issue
• Avoid driving aggressively until the issue is fixed
• Get the transmission checked by a professional mechanic
Check with the vehicle manufacturer for specific warranty coverage on transmission components.
This code has been associated with vehicles that have known issues with transmission solenoids.
Moderate – It is advisable to address this issue soon to prevent further transmission damage.
Driving with transmission issues can be unsafe and may cause further damage to the vehicle.
• Vehicle at operating temperature
• Transmission in drive mode
The pressure control solenoid 'D' is located inside the transmission, typically accessible by removing the transmission pan.
Q: Can I drive with a P1903 code?
A: It's not recommended to drive for long distances with this code, as it can cause further transmission damage.
Q: How do I know if the solenoid is bad?
A: Symptoms like harsh shifting and transmission slipping can indicate a bad solenoid. A professional diagnosis is recommended.
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