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 something is wrong with the part of the car that helps change gears. It's like a switch that isn't working right, so the car might not shift gears smoothly.
The transmission control module has detected a low voltage condition in the circuit for shift solenoid C, E, or F.
The P174A code is triggered when the transmission control module (TCM) detects a low voltage condition in the circuit for one of the shift solenoids (C, E, or F). These solenoids are responsible for controlling the flow of transmission fluid to change gears. A low circuit condition typically indicates a problem with the solenoid itself, the wiring, or the TCM.
• Harsh or delayed shifting
• Transmission stuck in one gear
• Check Engine Light illuminated
• Faulty shift solenoid
• Damaged wiring or connectors
• Faulty transmission control module (TCM)
Transmission Control Module (TCM): A computer that controls the transmission's operation.
Shift Solenoid: An electromechanical valve that controls the flow of transmission fluid.
• Use an OBD-II scanner to confirm the code.
• Inspect wiring and connectors for damage or corrosion.
• Test the shift solenoid for proper operation.
• Replace the faulty shift solenoid.
• Repair or replace damaged wiring or connectors.
• Replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Periodic inspection of wiring and connectors
• Avoid aggressive driving habits
Transmission Control Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for accurate diagnosis.
Check with the vehicle manufacturer for specific warranty coverage on transmission components.
This code has been associated with vehicles that have high mileage or inadequate maintenance of the transmission system.
Moderate – It should be addressed soon to avoid further transmission damage.
Driving with a faulty transmission can lead to unsafe driving conditions. Address this issue promptly.
• Vehicle at operating temperature
• Transmission in drive or reverse
The shift solenoids are located inside the transmission, typically accessible by removing the transmission pan.
Q: Can I drive with a P174A 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 P174A code?
A: After repairs, you can reset the code using an OBD-II scanner.
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