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 thinks the sensor that checks how hot the transmission fluid is, isn't working right. It's saying the temperature is too low, which might mean the sensor is broken or there's a wiring problem.
The P2742 code is triggered when the powertrain control module (PCM) detects a low voltage signal from the transmission fluid temperature sensor B, indicating that the sensor might be malfunctioning or there is an issue with the circuit.
The Transmission Fluid Temperature Sensor B is responsible for monitoring the temperature of the transmission fluid. This sensor sends a voltage signal to the PCM, which uses this information to adjust transmission operation for optimal performance. A low circuit signal indicates that the sensor is reading a temperature lower than expected, which could be due to a faulty sensor, wiring issues, or a problem with the PCM.
• Check Engine Light is on
• Transmission may not shift properly
• Poor fuel economy
• Faulty transmission fluid temperature sensor B
• Wiring issues such as short circuits or open circuits
• Faulty PCM (Powertrain Control Module)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the transmission fluid temperature sensor B
• Replace the transmission fluid temperature sensor B
• Repair or replace damaged wiring or connectors
• Replace or reprogram the PCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels
• Inspect wiring and connectors during routine maintenance
• Use high-quality transmission fluid
Sensor Issue
• Avoid driving the vehicle until the issue is fixed to prevent further damage
• Consult with a professional mechanic for accurate diagnosis
Check with the vehicle manufacturer to see if the transmission sensor is covered under warranty.
This code has been reported in various models, often due to sensor failure or wiring issues.
Moderate – It is advisable to address this issue soon to avoid potential transmission damage.
Driving with a faulty transmission sensor can lead to unsafe driving conditions. It is recommended to have the vehicle inspected and repaired promptly.
• Engine at operating temperature
• Vehicle in park or neutral
The transmission fluid temperature sensor B is typically located inside the transmission or mounted on the transmission housing.
Q: Can I drive with a P2742 code?
A: It's not recommended to drive with this code active, as it could lead to transmission damage.
Q: How do I reset the P2742 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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