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 is saying that a sensor inside the transmission is getting too hot.
This code indicates that the temperature sensor inside the Transmission Control Module (TCM) is reporting a temperature that is higher than normal.
The Transmission Control Module (TCM) monitors the internal temperature of the transmission using built-in sensors. Code P188B is triggered when the internal temperature sensor 'B' detects a temperature that exceeds the manufacturer's specified limit, indicating a potential overheating condition.
• Transmission overheating warning light
• Poor transmission performance
• Transmission slipping
• Transmission fluid level is too low
• Faulty temperature sensor
• Blocked transmission fluid cooler
TCM: Transmission Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check transmission fluid level and condition
• Inspect the wiring and connectors to the temperature sensor
• Test the temperature sensor for proper operation
• Refill or replace transmission fluid
• Replace faulty temperature sensor
• Clean or replace transmission fluid cooler
• OBD-II scanner
• Multimeter
• Transmission fluid pump
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels
• Ensure proper cooling system function
• Avoid aggressive driving habits
Sensor Issue
• Avoid driving the vehicle until the issue is resolved
• Consult a professional mechanic for diagnosis
Check vehicle warranty for coverage on transmission components
This code is often associated with vehicles that have high mileage or those that frequently tow heavy loads.
High – Continuing to drive with this condition can cause serious damage to the transmission.
Driving with an overheating transmission can lead to failure and may pose a safety risk.
• Vehicle at operating temperature
• Transmission under load
The TCM is usually located near the transmission or integrated within it.
Q: Can I drive with code P188B?
A: It's not recommended to drive with this code active, as it indicates overheating which can damage the transmission.
Q: How do I reset the P188B code?
A: After addressing the issue, use an OBD-II scanner to clear the code. If the problem persists, the code will reappear.
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