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 noticed a problem with how fast the engine and the transmission are spinning when the car is in reverse.
The vehicle's powertrain control module (PCM) detects a discrepancy between the turbine speed sensor and the engine speed sensor readings when the transmission is in reverse.
The P186A code is triggered when the PCM detects that the rotational speeds of the turbine and engine are not matching as expected when the transmission is in reverse gear. This can indicate a problem with the transmission's ability to properly engage reverse, a sensor malfunction, or an issue with the transmission control module.
• Check Engine Light illuminated
• Difficulty engaging reverse gear
• Poor transmission performance
• Unusual noises when reversing
• Potential slipping in reverse
• Faulty turbine speed sensor
• Faulty engine speed sensor
• Transmission control module (TCM) malfunction
• Wiring issues or poor connections
• Mechanical issues within the transmission
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code and check for other related codes.
• Inspect the wiring and connectors for the turbine and engine speed sensors.
• Test the turbine speed sensor and engine speed sensor for proper operation.
• Check the transmission fluid level and condition.
• Inspect the transmission for mechanical issues.
• Replace the faulty turbine speed sensor.
• Replace the faulty engine speed sensor.
• Repair or replace damaged wiring or connectors.
• Update or reprogram the transmission control module if needed.
• Repair mechanical issues within the transmission.
• OBD-II scanner
• Multimeter
• Basic hand tools
• Transmission fluid level checker
$200 - $1000
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission maintenance and fluid changes
• Routine inspection of wiring and connectors
• Timely repairs of any transmission issues
Transmission Performance
• Avoid driving in reverse until the issue is fixed.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with issues in vehicles with automatic transmissions, particularly in models with known sensor or wiring vulnerabilities.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with transmission issues can be unsafe and may lead to further vehicle damage.
• Vehicle in reverse gear
• Engine running
The turbine speed sensor is typically located inside the transmission, while the engine speed sensor is usually mounted on the engine block.
Q: Can I drive my car with a P186A code?
A: It's best to avoid driving in reverse until the issue is addressed to prevent further damage.
Q: Is a P186A code serious?
A: Yes, it can indicate a transmission issue that should be addressed to avoid further damage.
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