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 the part that helps change gears. It's like when your phone can't connect to the internet.
The P0861 code is triggered when the transmission control module (TCM) detects a low voltage or communication issue in the gear shift control module A communication circuit.
The gear shift control module is responsible for managing the gear shifting process. The communication circuit is used to send and receive signals between the module and the vehicle's main computer. A 'low' circuit condition indicates a voltage or signal issue, possibly due to wiring problems, a faulty module, or a poor connection.
• Check Engine Light illuminated
• Difficulty or inability to shift gears
• Transmission stuck in a single gear
• Faulty gear shift control module
• Damaged or corroded wiring/connectors
• Poor electrical connection in the circuit
Transmission Control Module (TCM): A computer that controls the operation of the transmission.
OBD-II Scanner: A device used to read diagnostic trouble codes from a vehicle.
• Use an OBD-II scanner to confirm the code.
• Inspect wiring and connectors for damage or corrosion.
• Test the gear shift control module for proper operation.
• Repair or replace damaged wiring/connectors.
• Replace the gear shift control module if faulty.
• Ensure all connections are secure and free of corrosion.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Dodge Ram
• Jeep Grand Cherokee
• Chrysler 300
• Regular maintenance checks of electrical systems.
• Ensure connectors are clean and secure.
• Avoid exposure to moisture and corrosion.
Transmission Communication Issue
• Do not ignore the Check Engine Light.
• Consult a professional mechanic if unsure.
• Avoid driving the vehicle if shifting issues occur.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with communication issues in vehicles with electronic transmission control systems.
Moderate – Should be addressed soon to avoid potential transmission damage.
Driving with transmission issues can be unsafe and may lead to further damage.
• Vehicle must be running.
• Transmission must be engaged.
The gear shift control module is typically located near the transmission or within the center console.
Q: Can I drive my car with a P0861 code?
A: It's not recommended as it may lead to further transmission damage or unsafe driving conditions.
Q: How do I clear a P0861 code?
A: After repairs, the code can be cleared with an OBD-II scanner. However, ensure the issue is resolved to prevent recurrence.
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