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 thinks the temperature reading from a sensor in the transmission is wrong or doesn't make sense.
The vehicle's computer detected an unusual or unlikely temperature reading from the transmission fluid temperature sensor 'B'.
The P186D code is triggered when the powertrain control module (PCM) receives a signal from the transmission fluid temperature sensor 'B' that falls outside the expected range. This can indicate an electrical issue, a faulty sensor, or an actual problem with the transmission fluid temperature.
• Check Engine Light is on
• Erratic or harsh shifting
• Transmission overheating
• Faulty transmission fluid temperature sensor 'B'
• Wiring issues such as shorts or open circuits
• Malfunctioning PCM or TCM
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the transmission fluid temperature sensor 'B' for proper operation.
• Replace the faulty transmission fluid temperature sensor 'B'.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM/TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Volkswagen Passat
• Audi A4
• Skoda Octavia
• Regularly check and maintain transmission fluid levels.
• Inspect wiring and connectors for damage periodically.
• Ensure the vehicle's cooling system is functioning properly.
Sensor Issue
• Avoid driving the vehicle if it shows signs of transmission issues.
• Have the vehicle inspected by a professional mechanic as soon as possible.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with transmission sensor issues in several vehicle models, often due to sensor failure or wiring problems.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with unresolved transmission issues can lead to vehicle damage and unsafe driving conditions.
• Engine running
• Transmission at operating temperature
The transmission fluid temperature sensor 'B' is typically located within the transmission housing or on the transmission valve body.
Q: Can I drive with a P186D code?
A: It's not recommended to drive with this code active, as it may lead to transmission damage.
Q: How do I reset the P186D code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, the code should not return.
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