Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means your car's computer is having trouble understanding messages about the power going into the transmission.
The vehicle's control module is monitoring the CAN (Controller Area Network) messages related to the transmission intake torque and has detected an issue.
The P173D code is triggered when the transmission control module (TCM) detects a fault in the communication of torque input data over the CAN bus. This data is crucial for the TCM to manage the transmission's operation efficiently.
• Check Engine Light is on
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty transmission control module
• CAN bus wiring issues
• Faulty sensors providing incorrect torque data
CAN: Controller Area Network, a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other without a host computer.
TCM: Transmission Control Module, an electronic device that controls the transmission.
• Scan the vehicle with an OBD-II scanner to confirm the code.
• Inspect the CAN bus wiring for any signs of damage or disconnection.
• Test the transmission control module for proper operation.
• Repair or replace damaged CAN bus wiring.
• Replace faulty sensors providing incorrect data.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• CAN bus analyzer
$200 - $800
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance and inspection of the vehicle's wiring.
• Ensure sensors are functioning correctly.
• Keep the vehicle's software up to date.
Communication Issue
• Avoid driving at high speeds until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
Check with the vehicle manufacturer for specific warranty coverage related to the transmission control module.
This code has been reported in vehicles with complex transmission systems that rely heavily on electronic control.
Moderate – While the vehicle may still be drivable, ignoring the issue could lead to more serious transmission problems.
Driving with a malfunctioning transmission can be dangerous. It is advised to address the issue promptly to ensure safety.
• Vehicle must be in a safe, stationary position.
• Ensure the engine is off before inspecting wiring.
The transmission control module is typically located near the transmission or within the engine bay.
Q: Can I drive my car with a P173D code?
A: It's possible, but not recommended as it may cause further damage to the transmission.
Q: Will a P173D code affect my car's performance?
A: Yes, it can lead to poor shifting and reduced fuel efficiency.
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