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 computer inside the car's transmission has detected a problem. It's like when your computer at home gets a virus and doesn't work right. The car's computer is getting confused because something is interfering with it.
The transmission control module (TCM) has detected an internal error related to interference, which has exceeded a predefined threshold.
The P172E code indicates that the transmission control module has registered an error due to interference or noise within its internal circuits. This interference has surpassed the acceptable limit set by the manufacturer, leading to potential transmission performance issues.
• Check Engine Light is on
• Transmission shifting issues
• Reduced fuel efficiency
• Faulty transmission control module
• Electrical interference from other vehicle systems
• Wiring issues or poor connections
Transmission Control Module (TCM): A computer that controls the transmission's functions.
Interference: Unwanted signals that disrupt normal operation.
• Scan the vehicle for additional trouble codes
• Inspect the wiring and connections to the TCM
• Test the TCM for proper operation
• Replace or reprogram the transmission control module
• Repair or replace damaged wiring
• Ensure proper grounding and shielding of electrical components
• OBD-II scanner
• Multimeter
• Wiring diagram
$300 - $1200
Difficult
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance of electrical systems
• Avoid aftermarket electrical modifications
• Ensure proper installation of electronic devices
Transmission Control Module Issue
• Avoid driving the vehicle until repaired
• Consult a professional mechanic for diagnosis
• Consider a tow to the repair shop if symptoms are severe
Check with the vehicle manufacturer for warranty coverage on electronic components.
This code has been associated with vehicles that have complex electronic systems where interference is more likely.
High – This issue can lead to severe transmission problems if not addressed promptly.
Driving with this code can lead to unsafe driving conditions. It is recommended to address the issue immediately.
• Vehicle at operating temperature
• Transmission in all gear ranges
The transmission control module is typically located near the transmission or under the dashboard.
Q: Can I drive with a P172E code?
A: It's not recommended to drive with this code as it can cause serious transmission issues.
Q: What causes interference in the TCM?
A: Interference can be caused by faulty wiring, poor grounding, or electronic devices emitting signals.
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