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 having trouble talking to other parts of the car. Imagine if your phone couldn't send messages to your friend's phone; it's kind of like that.
The P1747 code indicates that there is an issue with the Controller Area Network (CAN) bus communication system in the vehicle.
The CAN bus is a vehicle bus standard that allows microcontrollers and devices to communicate with each other without a host computer. The P1747 code is set when the transmission control module (TCM) detects a malfunction in the CAN bus communication, which can affect the transmission operation.
• Check Engine Light is on
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty wiring or connections in the CAN bus
• Defective control module
• Interference or noise in the CAN bus line
CAN Bus: Controller Area Network Bus, a robust vehicle bus standard designed to allow microcontrollers and devices to communicate with each other.
TCM: Transmission Control Module, a device that controls modern electronic automatic transmissions.
• Use an OBD-II scanner to confirm the code
• Inspect the CAN bus wiring and connections for damage
• Test the control modules for proper operation
• Repair or replace damaged wiring or connectors
• Replace faulty control module
• Ensure proper grounding and shielding of the CAN bus
• OBD-II scanner
• Multimeter
• Wiring diagram
$150 - $600
Moderate
• Ford F-150
• Toyota Camry
• Honda Accord
• Regular maintenance checks
• Avoiding aftermarket electronic modifications
• Ensuring clean and secure electrical connections
Communication Error
• Do not ignore the Check Engine Light
• Avoid driving the vehicle until diagnosed
• Consult a professional mechanic
Check with your vehicle manufacturer to see if the CAN bus system is covered under warranty.
The P1747 code has been more commonly reported in vehicles with high mileage or those that have undergone electrical modifications.
Moderate – It is advisable to address this issue soon to avoid potential transmission problems.
Driving with a malfunctioning CAN bus system can lead to unpredictable vehicle behavior and is not recommended.
• Engine running
• Vehicle in park or neutral
The CAN bus wiring is typically located within the vehicle's main wiring harness, running throughout the vehicle.
Q: What is a CAN bus?
A: A CAN bus is a communication system in cars that allows different parts of the car to talk to each other.
Q: Can I drive with a P1747 code?
A: It's not recommended to drive with this code as it can lead to more serious transmission issues.
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