OBD-II Generic Error Code P2743: How to Fix It

Q: Can I drive my car with a P2743 code?

It depends on the cause. If the sensor is faulty but the transmission is actually functioning normally and shifting smoothly, you may be able to drive short distances to a shop. However, if the code reflects genuine overheating — especially if you notice harsh shifting, slipping, or a burnt fluid smell — you should stop driving immediately to prevent serious transmission damage. When in doubt, have the vehicle towed to a shop.

Q: What is the difference between TFT Sensor A and TFT Sensor B?

Many modern automatic transmissions have more than one fluid temperature sensor monitoring different locations or circuits within the transmission. Sensor A (P2742) monitors one circuit, while Sensor B (P2743) monitors a second, separate circuit. They serve the same basic function but are wired and located independently. Code P2743 specifically points to the 'B' sensor circuit reading a high voltage, which typically corresponds to an open circuit in the sensor or wiring.

Q: How much does it cost to fix a P2743 code?

If the fix is simply replacing TFT Sensor B, the part typically costs between $20 and $80 depending on the vehicle, and labor at a shop can range from $75 to $200, making the total repair roughly $100–$280. If the issue involves wiring repair, a transmission fluid service, or addressing a genuine overheating problem (cooler lines, radiator, etc.), costs can rise significantly — from $200 to over $1,000 depending on the underlying cause.

Q: Will P2743 clear itself after fixing the problem?

No. After repairing the underlying fault, you must use an OBD-II scanner to manually clear the stored trouble code. If you do not clear it, the check engine light will remain on even after the repair is complete. Some vehicles may eventually clear the code on their own after a number of successful drive cycles without the fault recurring, but this can take days or weeks of driving — clearing it manually with a scanner is the fastest and most reliable approach.

Q: Can low transmission fluid cause a P2743 code?

Indirectly, yes. Low transmission fluid reduces the fluid's ability to absorb and dissipate heat, which can cause the transmission to genuinely overheat and trigger a high-temperature reading on the sensor. Additionally, low fluid levels can sometimes expose a temperature sensor that is normally submerged, causing an abnormal reading. Always check and correct the transmission fluid level as one of the first steps when diagnosing P2743.

Abstract

Error code P2743 means your vehicle's powertrain control module (PCM) has detected an abnormally high voltage signal from Transmission Fluid Temperature (TFT) Sensor B, which monitors the temperature of the fluid inside your automatic transmission. This could indicate a faulty sensor, damaged wiring, or — in more serious cases — transmission fluid that is actually overheating. Addressing this code promptly is important because running a transmission at extreme temperatures can cause significant internal damage over time.