Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer that controls the transmission has detected a problem inside itself. It's like when a computer has a glitch and doesn't work right.
The Transmission Control Module (TCM) has detected an internal error related to interference levels, which are below the expected threshold.
P17B4 indicates that the Transmission Control Module (TCM) has identified a Level 2 error due to interference levels being below the required threshold. This could be due to electrical noise or a fault within the TCM itself, affecting its ability to manage the transmission effectively.
• Check Engine Light is on
• Transmission may not shift properly
• Reduced vehicle performance
• Faulty Transmission Control Module
• Electrical interference or noise
• Wiring issues or poor connections
Transmission Control Module (TCM): A computer that controls the transmission functions in a vehicle.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics and reporting in vehicles.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connections to the TCM
• Test the TCM for proper operation
• Replace or repair the faulty TCM
• Address any wiring or connection issues
• Clear the code and test drive the vehicle
• OBD-II Scanner
• Multimeter
• Basic hand tools
$300 - $1200
Moderate
• Audi A4
• Volkswagen Passat
• Skoda Superb
• Regularly inspect and maintain vehicle wiring
• Avoid exposure to high electromagnetic fields
• Ensure regular vehicle servicing
Transmission Control Module Issue
• Avoid driving long distances until repaired
• Consult a professional mechanic
• Monitor for any new symptoms
Check with the vehicle manufacturer for warranty coverage on the TCM.
This code has been associated with issues in vehicles with complex electronic control systems, particularly in European models.
Moderate – Should be addressed soon to prevent further transmission issues.
Driving with a faulty TCM can lead to unsafe driving conditions. Address the issue promptly.
• Vehicle must be running
• Transmission must be in operation
The Transmission Control Module is typically located near the transmission or inside the engine bay.
Q: Can I drive with a P17B4 code?
A: It's not recommended to drive for long distances as it may lead to further transmission issues.
Q: How do I clear a P17B4 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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