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 getting a strange signal from the gear shifter when it tries to change gears. It's like when a remote control sends the wrong signal to the TV.
The transmission control module (TCM) is detecting an incorrect frequency signal from the gear shift position sensor for gears 5 and 3.
The P174C code indicates that the transmission control module has detected an abnormal frequency in the signal from the gear shift position sensor when shifting between the 5th and 3rd gears. This can be due to an electrical issue, such as a faulty sensor or wiring problem, that affects the signal's frequency.
• Check Engine Light is on
• Erratic shifting
• Transmission stuck in one gear
• Faulty gear shift position sensor
• Wiring issues in the gear shift circuit
• Malfunctioning transmission control module
Transmission Control Module (TCM): A computer that controls the automatic transmission.
Gear Shift Position Sensor: A sensor that detects the position of the gear shifter.
• Use an OBD-II scanner to confirm the code.
• Inspect the gear shift position sensor and its wiring.
• Test the transmission control module for faults.
• Replace the gear shift position sensor if faulty.
• Repair or replace damaged wiring in the gear shift circuit.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Wiring repair kit
$150 - $500
Moderate
• Ford Focus
• Mazda 3
• Chevrolet Cruze
• Regular maintenance of the transmission system
• Periodic inspection of wiring and connectors
• Timely replacement of faulty sensors
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check if the vehicle's powertrain warranty covers transmission-related issues.
This code has been reported in vehicles with electronic transmission control systems, especially in models with complex gear shift mechanisms.
Moderate – It should be addressed soon to prevent transmission damage.
Driving with transmission issues can be unsafe and may lead to further mechanical damage.
• Vehicle in park or neutral
• Engine running and warmed up
The gear shift position sensor is typically located on the transmission housing or near the gear shifter assembly.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to more severe transmission issues and potential safety hazards while driving.
Q: Can I fix this issue myself?
A: If you have automotive repair experience, you might be able to fix it, but it's recommended to seek professional help for accurate diagnosis and repair.
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