Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's computer is saying that a part that helps change gears isn't getting enough power. It's like when a toy doesn't have enough batteries to work properly.
The code P174B indicates that the transmission control module has detected a low voltage condition in the circuit that controls the shift solenoids 'A' or 'B'.
Shift solenoids are responsible for controlling the flow of transmission fluid to change gears in an automatic transmission. A 'Circuit Low' condition means that the electrical circuit is not receiving the expected voltage, which can prevent the solenoids from operating correctly.
• Transmission slipping
• Harsh or delayed shifting
• Illuminated check engine light
• Faulty shift solenoid
• Wiring issues such as shorts or open circuits
• Faulty transmission control module
Shift Solenoid: An electromechanical device in the transmission that controls fluid flow to change gears.
Transmission Control Module: A computer that controls the automatic transmission.
• Use a scan tool to verify the code and check for any other related codes.
• Inspect the wiring and connectors for damage or corrosion.
• Test the shift solenoids for proper operation and resistance.
• Repair or replace damaged wiring or connectors.
• Replace the faulty shift solenoid.
• Replace or reprogram the transmission control module if necessary.
• OBD-II scan tool
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Inspect wiring and connectors periodically
• Avoid aggressive driving habits
Transmission Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for a thorough diagnosis.
Check with your vehicle manufacturer for transmission warranty coverage.
This code has been reported in vehicles with high mileage or those with poor maintenance records.
Moderate – It is advisable to address this issue soon to prevent further transmission damage.
Driving with transmission issues can lead to unsafe driving conditions. It is recommended to repair the 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 oil pan.
Q: Can I still drive my car with this code?
A: It's not recommended as it can lead to further transmission damage and unsafe driving conditions.
Q: How can I prevent this issue?
A: Regular maintenance and avoiding aggressive driving can help prevent transmission issues.
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