Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the electrical part of a device in your car that helps control the pressure of the transmission fluid. Think of it like a light switch that isn't working right.
The P173A code indicates an issue with the electrical circuit that controls the pressure control solenoid 'A' in the transmission.
The pressure control solenoid 'A' is responsible for regulating hydraulic pressure within the transmission. An electrical fault in its control circuit can lead to improper transmission operation. This code is triggered when the transmission control module (TCM) detects a malfunction in the solenoid's circuit.
• Erratic or harsh shifting
• Transmission slipping
• Check Engine Light illuminated
• Faulty pressure control solenoid 'A'
• Damaged wiring or connectors
• Faulty transmission control module (TCM)
Solenoid: An electromechanical device that converts electrical energy into mechanical movement.
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
• Use an OBD-II scanner to confirm the code.
• Inspect wiring and connectors for damage or corrosion.
• Test the pressure control solenoid 'A' for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the pressure control solenoid 'A' if faulty.
• Replace or reprogram the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford Focus
• Chevrolet Malibu
• Honda Accord
• Regular transmission fluid changes
• Routine inspection of wiring and connectors
• Avoid aggressive driving habits
Transmission Control Issue
• Avoid driving aggressively until the issue is resolved.
• Get the vehicle inspected by a professional mechanic.
Check if your vehicle's powertrain warranty covers transmission components.
This code has been associated with transmission performance issues in vehicles with electronic control systems.
Moderate – Address the issue to prevent further transmission damage.
Driving with a malfunctioning transmission can lead to safety issues. Address the problem promptly.
• Vehicle at operating temperature
• Transmission in drive mode
The pressure control solenoid is located inside the transmission, often accessible by removing the transmission pan.
Q: Can I drive with a P173A code?
A: It's not recommended to drive for extended periods with this code as it can lead to further transmission damage.
Q: How can I prevent this code from appearing?
A: Regular maintenance and avoiding aggressive driving can help prevent this issue.
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